| T.R | Title | User | Personal
Name | Date | Lines |
|---|
| 1113.43 | Airfoil Coordinates | CLOSUS::TAVARES | John -- Stay low, keep moving | Mon Jun 05 1989 14:18 | 18 |
| Tom, I don't have it handy, but last Fall MA published a series
on dihedral. I think the first article explained all that.
On airfoils, MB's free flight columnist Bob Stalick publishes a
"Darn Good Airfoil" each month. He has a compilation of these
foils that can be ordered from:
Bob Stalick
5066 Picadilly Circle
Albany OR, 97321
Copies are $2.50 plus $1 postage and handling.
Bob's book gives airfoil coordinates for lots of foils, some old,
some exotic, all from the free flight standpoint.
Also, I have a fair collection of airfoil coordinates, once you
decide on one, let me know, I may have the listing for you.
|
| 1113.44 | reasonable book on theory | LEDS::COHEN | | Mon Jun 05 1989 16:54 | 23 |
|
Tom,
There is a book titled "Model Airplane (or Aircraft) Aerodynamics".
It's usually advertised in the back of magazines where you find books
advertised. The cover of the book has a drawing of an ASW-style glider
on it. It's paperback.
I own this book (But I've lent it to so many people I don't know where
it is anymore). It's an excellent classroom style textbook on
areodynamics as applied to models. Scale effects, Reynolds numbers,
L/D, all that good stuff is discussed. The back of the book has a
number of airfoil plots (like > 30, probably, if I recall). Some of the
newer foils like the E195 are missing (the book is from the late 60s, I
think). But still, this is the best book for a reasonable to understand
in-depth technical discussion of aerodynamics.
I strongly reccomend it.
It will satisfy your need.
Randy
|
| 1113.45 | book on wing sections | GIDDAY::CHADD | Pylon; the ultimate High. | Mon Jun 05 1989 20:15 | 13 |
| Tom,
I think I have mentioned it before but an excellent book is
"Theory of Wing Sections" by Ira H. Abbot and Albert E. Von Doenhoff
Published by Dover Publications, Inc. New York
Standard Book No: 486-60586-8. US$6.50????
It goes into High Lift Devices, aerodynamic characteristics, compressibility,
effects of viscosity and all those good things. It's heavy going in places
but it contains 700 pages of good info..
John
|
| 1113.1 | S3021 & S4061 | K::FISHER | Stop and Smell the Balsa! | Fri Sep 29 1989 12:09 | 197 |
| From: ms2@psuecl.bitnet
Subject: Re: Power Airfoils.
Date: 28 Sep 89 00:14:04 GMT
In article <3834@unix.SRI.COM> henry@ginger.sri.com writes:
>Airfoil efficiency isn't nearly as important to the power crowd as
>it is to the sailplane bunch. A perfect example is the "Roun' Tuit",
>an airplane which has a square-edged disk for a wing. It's supposed
>to fly fine. With a big motor on the front, drag reduction becomes
>a secondary concern for a power plane design. More important are a
>wide speed range, stability (both static and dynamic), and stall-spin
>characteristics, both at high speed and low speed.
You are correct that low drag is not necessarily essential to power flying.
You can always add a larger engine to compensate for an inefficient airfoil.
For some types of flying, however, low drag is important
as for example in racing. I believe there are restrictions placed on the engine
size. When everybody in the competition has the same engine (the best), the race
will be determined by the airfoil among other things. I continue to be amazed
at how slowly Formula 1 racing has evolved in terms of the aerodynamics. The
planes all look the same. (Is there a restriction on how the plane looks?)
>A power plane with an extremely efficient wing would fly very fast
>and would be hard to slow down. Would this be an advantage to pattern
>fliers? I don't know.
This is a good question, and one that is frequently over looked when so many
people are talking about low drag. For pattern flying a slick, clean and fast
airfoil is not wanted. Instead, a broad speed range is need. This is still
an airfoil design problem. Chances are since most of the airfoils out there
are of the cut-and-try variety there are substantial improvements to be had.
>It seems as though serious power airfoils must be symmetrical by
>definition. This is a pretty big constraint. Can symmetrical airfoils
>be improved? What about variable-camber airfoils for power applications?
>Will the pattern transmitters of the future have an "invert" button?
Symmetric airfoils are no more difficult to design then cambered ones.
My answers: Yes. Too open ended to answer. Why not?
>I'd be interested in hearing from the high-performance pattern people
>just what it is that makes a good plane, and what the deficiencies with
>today's models are. And I'd like to see what thoughts Michael has on
>how his approach could address these deficiencies.
I am waiting too. As mentioned, I think speed range is most important
for the pattern people. And I would add that they might need a lot of drag
for some manuevers.
I guess I should say that my approach deals with the whole airfoil
design problem. For sailplane airfoils, you need a certain range
of lift depending on the required speed range. Once this is obtained,
then an all out effort is made to lower the drag. The sailplanes push the
limit in the area of low drag, whereas; I suspect that pattern planes
push the limit in the broad lift range area.
Michael Selig
233 Hammond Bldg.
University Park, PA 16802
From: ms2@psuecl.bitnet
Subject: S3021 and S4061 airfoil coordinates
Date: 28 Sep 89 00:16:26 GMT
Pat Chewning asked me to post the coordinates for the S3021 and S4061
RC sailplane airfoils.
S3021
1.00000 0.0
0.99663 0.00039
0.98679 0.00172
0.97104 0.00419
0.94996 0.00769
0.92398 0.01193
0.89336 0.01670
0.85840 0.02198
0.81959 0.02776
0.77748 0.03393
0.73266 0.04038
0.68572 0.04694
0.63730 0.05341
0.58801 0.05954
0.53839 0.06504
0.48891 0.06964
0.43996 0.07312
0.39190 0.07536
0.34513 0.07632
0.29999 0.07596
0.25685 0.07433
0.21611 0.07151
0.17816 0.06753
0.14331 0.06243
0.11182 0.05631
0.08392 0.04930
0.05983 0.04156
0.03968 0.03329
0.02358 0.02472
0.01160 0.01615
0.00374 0.00799
0.00008 0.00099
0.00191 -0.00427
0.00984 -0.00852
0.02320 -0.01232
0.04178 -0.01547
0.06542 -0.01789
0.09395 -0.01957
0.12712 -0.02053
0.16464 -0.02085
0.20614 -0.02059
0.25118 -0.01986
0.29928 -0.01876
0.34988 -0.01742
0.40237 -0.01592
0.45612 -0.01433
0.51047 -0.01273
0.56476 -0.01115
0.61834 -0.00963
0.67056 -0.00821
0.72079 -0.00690
0.76840 -0.00570
0.81283 -0.00462
0.85355 -0.00365
0.89005 -0.00278
0.92187 -0.00193
0.94876 -0.00107
0.97048 -0.00035
0.98660 0.00003
0.99661 0.00006
1.00001 -0.00000
S4061
1.00000 0.0
0.99675 0.00034
0.98709 0.00147
0.97129 0.00363
0.94977 0.00698
0.92304 0.01156
0.89171 0.01729
0.85637 0.02403
0.81765 0.03151
0.77610 0.03945
0.73227 0.04752
0.68665 0.05541
0.63971 0.06283
0.59189 0.06949
0.54359 0.07519
0.49522 0.07974
0.44716 0.08301
0.39979 0.08491
0.35348 0.08542
0.30862 0.08453
0.26554 0.08227
0.22460 0.07876
0.18619 0.07414
0.15074 0.06848
0.11855 0.06186
0.08988 0.05437
0.06493 0.04616
0.04385 0.03741
0.02676 0.02838
0.01380 0.01937
0.00502 0.01069
0.00046 0.00283
0.00079 -0.00320
0.00681 -0.00787
0.01835 -0.01209
0.03499 -0.01545
0.05666 -0.01780
0.08329 -0.01907
0.11475 -0.01932
0.15086 -0.01864
0.19130 -0.01724
0.23566 -0.01527
0.28346 -0.01291
0.33414 -0.01034
0.38708 -0.00771
0.44161 -0.00516
0.49704 -0.00279
0.55267 -0.00069
0.60777 0.00107
0.66164 0.00245
0.71357 0.00342
0.76289 0.00400
0.80895 0.00419
0.85115 0.00405
0.88894 0.00363
0.92184 0.00301
0.94940 0.00225
0.97127 0.00146
0.98714 0.00074
0.99678 0.00020
1.00001 -0.00000
Michael Selig
233 Hammond Bldg.
University Park, PA 16802
|
| 1113.2 | books and programs... | K::FISHER | Stop and Smell the Balsa! | Mon Oct 02 1989 17:06 | 119 |
| From: ms2@psuecl.bitnet
Subject: Re: Where is SOARTECH ?
Date: 29 Sep 89 01:45:11 GMT
In article <1191@noao.UUCP> dat@noao.edu writes:
>A friend recently asked me for the information on how to obtain
>the SOARTECH booklets (manuals, bulletins, whatever). Would
>someone directly related to SOARTECH please post the current
>address, prices, and availability.
(I have been waiting for this one.)
The Soartech series may be obtained from the publisher:
H. A. Stokely
1504 North Horseshoe Circle
Virginia Beach, VA 23451
Soartech is an RC soaring technical journal that is written by
those having something to contribute to the sport.
Generally the articles are more technical than those found in the magazines.
It is a non-profit operation.
All editions, except the latest (Soartech 8), are photocopied by Herk
in his garage.
For availabilty and prices, Herk should be contacted directly.
I have made a personal contribution to the most recent edition. See below:
*******************************************************************************
* AIRFOILS AT LOW SPEEDS by Michael Selig, John Donovan, and David Fraser
-- A special edition of Soartech published by Herk Stokely
through the non-profit initiative of the Tidewater Model Soaring Society.
* Soartech 8 is available from: Herk Stokely
1504 N. Horseshoe Circle
Virginia Beach, VA 23451
* Over 60 wind tunnel models tested at Princeton University
* Over 130 polars generated
* 54 different airfoils tested as listed below
* 400 pages of text, data plots, graphs,
tabulated performance data and airfoil coordinates
* Reynolds numbers tested: 60k, 100k, 150k, 200k, 300k
* $15 continental USA & Canada, $20 overseas surface, $30 overseas air.
* Airfoils tested: AQUILA FX63-137 S3014 SD7037
CLARK-Y HQ2/9 S3016 SD7043
DAE51 J5012 S3021 SD7062
DF101 M06-13-128 S4061 SD7080
DF102 MB253515 S4062 SD7084
DF103 NACA 0009 S4180 SD7090
E193 NACA 2.5411 S4233 SD8000
E193MOD NACA 64A010 SD2030 SD8020
E205 NACA 6409 SD2083 SD8040
E214 RG15 SD5060 SPICA
E374 S2048 SD6060 WB135/35
E387 S2055 SD6080 WB140/35/FB
FLAT PLATE S2091 SD7003
FX60-100 S3010 SD7032
* Excerpted from the book:
The history of this experimental program on low-speed airfoils is
extensive. In August 1986, work toward testing model sailplane airfoils in
a wind tunnel at Princeton University began on an ambitious scale. The
initial plan was to test 30 airfoils: 15 existing airfoils and 15 new
airfoils to be designed concurrently with the test. As news of the project
caught the attention of radio control model soaring enthusiasts, the
project grew far beyond the original goals and expectations, thanks to
their generosity. When the experimental apparatus was finally dismantled
in January 1989, almost two and a half years later, over 60 models were
tested and over 130 airfoil polars were generated. It is our hope that the
results of this work will be valuable to modelers and researchers for many
years to come.
******************************************************************************
* LOW REYNOLDS NUMBER AIRFOIL VIDEO (VHS)
* Available from: John Donovan
754 Stone Canyon Dr.
Manchester, MO 63021
* Approximately 30 minutes long
* $20 continental USA & Canada
* Summary:
To offset some of the debt incurred during the testing phase of this
project, a video tape was made to document the experiments and
explain some of the aerodynamics of model airplane airfoils.
The wind tunnel, measurement apparatus, and test procedure are explained
showing the tunnel and data taking in operation.
The effects of the drag-producing laminar separation bubbles
are explained. Through specific examples, airfoils well suited for
F3B, multi-task, and cross-country flying are discussed.
*******************************************************************************
* AIRFOILS AT LOW SPEEDS DATA DISK
* Available from: David B. Fraser
1335 Slayton Drive
Maple Glen, PA 19002
* Airfoil performance data and coordinates on computer disk as ASCII files
* IBM 3 1/2 inch and 5 1/4 inch disks, and Macintosh
* $12 continental USA & Canada
*******************************************************************************
* Selected References:
Flying Models June 88, p. 69
Jan 89, p. 66
April 89, p. 71
July 89, p. 64
Sept 89, p. 64
Oct 89, p. 66, 67
Model Aviation Aug 88, p. 169, 172
Aug 89 p. 168, 169
Sept 89, p. 40
Oct 89, p. 48
Model Builder Nov 88, p. 38, 39, 105
Dec 88, p. 40, 41, 42, 43
Feb 89, p. 88, 89
Aug 89, p. 93
*******************************************************************************
* Please feel free to pass this information along,
since there is no formal advertising.
******************************************************************************
Michael Selig
233 Hammond Bldg
University Park, PA 16802
|
| 1113.3 | NACA 2412 info and misc questions | K::FISHER | Stop and Smell the Balsa! | Thu Oct 05 1989 19:17 | 85 |
| From: ms2@psuecl.bitnet
Subject: Re: Airfoils for Electrics.
Date: 4 Oct 89 01:16:49 GMT
In article <9680@cadnetix.COM> waynea@cadnetix.COM (Wayne Angevine) writes:
>The discussion about power airfoils got me thinking. What airfoils
>would be good for electric sport planes? Most of those that I have
>seen in magazines use the NACA 2412. Are there better choices?
The NACA 2412 is pretty good, except the 2-D stall is kind of nasty.
This is only a problem if the lift distribution is very near elliptic.
(In the elliptic case the downwash is constant only the span so the
airfoils are at the same angle of attack, thus the stall is like
the two-dimensional stall. With big tip chords there is a lot of downwash,
so the stall happens inboard first and gives a smoother stall
in spite of otherwise nasty 2_d stall behavior.)
There are two approaches that can be taken when selecting an airfoil.
First, say airfoil X (NACA 2412) works well, but some airfoil Y with a little
more lift or lower drag or [insert your favorite here] would be better.
This is the long path to optimization.
Second, say you want to fly 50 mph max and stall at 15 mph and do it at
a wing loading of 12 oz/ft**2 for a 10 inch average chord. This is the kind
of information that gives the lift range of the airfoil and the
Reynolds Number range of operation. With this you can crack a book
of airfoil data and pick the airfoil with the lowest drag/best stall/
low moment/.... or run an airfoil design code and design a new airfoil.
I have not specifically designed an airfoil to out perform the NACA 2412.
Taking th first approach, what would you like to see improved on the
NACA 2412?
>I assume that the requirements are that it provide a high max. lift
>coefficient, but also generate reasonable lift at negative angles
>of attack (that is, inverted flight.) Michael, are any of your
>glider airfoils candidates?
Is inverted flight really important, because it will cost a lot
in terms of normal level flight performance?
No good glider airfoil is a candidate for efficient inverted flying.
>Another thought about airfoils: Most of the current work seems to
>be on laminar flow airfoils. I have heard people contend that some
>of these airfoils don't work as well in practice as they do in wind
>tunnels, particularly because it is very difficult to get a precise
>section with most building techniques. Is anybody working on airfoils
>optimized to be used with built-up construction? Is it possible to
>design an airfoil with high performance *and* good tolerance to section
>variations?
In the general aviation area, the push is towards more laminar flow.
For low Reynolds numbers (model aviation), the trouble is that the air flow
is too stable. It WANTS TO BE LAMINAR. The trick is making it TURBULENT
in order to reduce the size of the laminar separation bubble.
My suggestion is to forget everything that you have heard about general
aviation airfoils, unless you understand airfoil aerodynamics real well.
The speed range of model vs full-scale is very different, and consequently the
behavior of the boundary layer is also very different!
You are correct that the accuracy of some airfoils (for general avaition
application) is critical. The tolerance to airfoil inaccuracies is airfoil
dependent. I spent this past summer at NASA Langley working with Dan
Somers on the design of a new natural-laminar-flow airfoil [NLF(1)-0115]
for general aviation applications (wait till the homebuilders get a load
of this airfoil). One of the design requirements was that the airfoil
performance not be dramatically diminished by slight variations in the
contour. The airfoil was designed specifically to suit the needs (and abilities)
of the growing number of homebuilders.
There may be a big difference between airfoil performance on built-up (open-bay)
construction and the full-sheeted construction. If a model is advertised
as using a specific airfoil, but the construction is built up, then
beware! Evidently the (now) ACE R/C Prodigy 2M sailplane works very well
with the S4061 on built-up construction. I have one of these gliders
myself, but I only bought a kit because the sailplane proved its worth
at the NATS a few years ago.
I hope this helps.
Michael Selig
Dept. of Aerospace Eng.
233 Hammond Bldg.
University Park, PA 16802
e-mail: ms2@psuecl.bitnet
|
| 1113.4 | Airfoil Accuracy | K::FISHER | Stop and Smell the Balsa! | Wed Oct 11 1989 10:51 | 66 |
| From: ms2@psuecl.bitnet
Subject: Re: Airfoils for Electrics.
Date: 9 Oct 89 23:51:55 GMT
In article <9712@cadnetix.COM> waynea@cadnetix.COM (Wayne Angevine) writes:
>>For low Reynolds numbers (model aviation), the trouble is that the air flow
>>is too stable. It WANTS TO BE LAMINAR. The trick is making it TURBULENT
>>in order to reduce the size of the laminar separation bubble.
>This is interesting. Are your airfoils designed to have turbulent flow?
>In what range of lift coefficients? (I have read your old Soartech
>paper, but I don't remember much discussion of your design criteria,
>other than avoiding bubble formation.)
To speak of the airfoils as being turbulent or laminar flow airfoils is
too simplistic. The flow is laminar over the forward part of the airfoil
then makes a transition to turbulent flow through the laminar separation
bubble. The bubble may be very long or short depending on the condition.
A bubble that is 10% of chord is not that unusual.
The airfoils in Soartech were mainly designed for RC sailplanes.
This particular application requires low drag at positive lift coefficients,
and the airfoil should be on the order of 10% thickness for today's building
techniques and styles of flying.
>>You are correct that the accuracy of some airfoils (for general avaition
>>application) is critical.
>Is this also true for model airfoils?
It is a function of the pressure gradients on the airfoil. Chances
are over the areas where the gradients are steep, the sensitivity to
errors in contour are largest. The whole thing is not understood well.
>>There may be a big difference between airfoil performance on built-up
>>construction and the full-sheeted construction.
>Can you outline these differences and their causes? In particular,
>are the differences due to the varying shape of the airfoil as you
>go out along the span, or to the inaccurate shape of the section?
>Is it more important to have a uniform airfoil or an accurate one?
Not really. If one is concerned enough to think about the problems with
open bay construction, then the best solution is to avoid the problem
and build an accurate full-sheeted wing.
The varying shape caused by the open-bay construction will increase the
induced drag. Independent of this, the inaccurate airfoil shape is bad.
>Just so you will know where I'm coming from, I got most of my ideas
>from reading Martin Simons' "Model Aircraft Aerodynamics" and from
>the RC magazines (the aerodynamics-related content of which is at
>least half crap, and I hope I can tell which half.) I'm an
>electrical engineer, no formal aerodynamics training. Are there
>any fundamental ideas in Simons which are incorrect?
Sorry, I have not read Martin Simons book (but I do have it).
I hope all that help.
Michael Selig
Dept. of Aerospace Eng.
233 Hammond Bldg.
University Park, PA 16802
e-mail: ms2@psuecl.bitnet
|
| 1113.5 | Turbulent airflow | TEKTRM::REITH | Jim Reith DTN 235-8459 HANNAH::REITH | Wed Oct 11 1989 12:10 | 6 |
| One technique I've seen used was to have a thread strung in front of the leading
edge to induce turbulence around the wing. I never tried it but some pilot's I
flew gliders with in my younger days swore by it and consistantly found better
air than I at the same hill.
Comments from the peanut gallery?
|
| 1113.6 | new airfoils mandate foam? | CTD024::TAVARES | John -- Stay low, keep moving | Wed Oct 11 1989 13:38 | 7 |
| Been doing a lot of research about foam wings lately, and I seem
to remember the remark, I think it was by the Model Builder
glider columnist that these new airfoils, including the Epplers,
can only be executed in foam. The columnist said that the
offsets are so critical that you cannot, even by an expert with a
jig-built wing, properly reproduce them with built-up
construction.
|
| 1113.7 | | LEDS::COHEN | Some limitations may apply... | Thu Oct 12 1989 15:22 | 24 |
| Re. .5, Turbulence.
The "device" you describe is known as a Turbulator. It causes
turbulence along the boundary layer of air that flows across the wing,
resulting it reduced drag and reduced airflow separation. This improved
airfoil efficiency occurs
becuase the turbulence results in the laminar flow becoming established
further back on the wing, causing the separation bubble that forms
on the back half of the upper surface of the airfoil to appear closer
to the trailing edge.
A more durable Turbulator can be made by affixing a
serrated-edge-forward strip of balsa across the top of the leading edge
of the wing.
Articles/books I've read about airfoils all say about the same thing,
the Turbulator reduces the separation bubble considerably, resulting in
lowered drag, and increased airfoil efficiency (more lift).
I read once, somewhere, a guy claiming that the "textured" covering
materials induce some of the Boundary Layer turbulence of the
Turbulator. He claimed that the same identical glider, covered with
smooth covering like MonoCote, performed noticably poorer than when it
was covered with one of the fabric type coverings.
|
| 1113.8 | Help my minds eye | RVAX::SMITH | | Thu Oct 12 1989 16:02 | 14 |
| Can you go into a little more detail on the serrated balsa strip.
Like how big are we talking? When you say "along the top of the
leading edge", can you be a little more specific as to placement
and should the piece of balsa be shaped to conform to the wing.
If a textured covering is enough to induce turbulence, what might
happen if, say, drops of thick CA were placed all along the leading
edge. For example, in the case of a built up wing, what might happen
if you covered the sheeted section of the leading edge with little
bumps? Lastly, does this apply at all to flat bottom wings?
Thanks,
Steve
|
| 1113.9 | Postcript (TM) airfoils | SHTGUN::SCHRADER | CSS::SCHRADER=264-4170=MK01/2K12 | Thu Oct 12 1989 20:17 | 292 |
| Well, I got really curious about what these airfoils looked like so I made
the following Postscript program to print them out. Just extract the following,
cut out this leading text, and send it to your favorite PS printer. It would
be a trivial change to make this print out sets of tapered rib templates or
templates for a foam cutter. Enjoy...
===============================================================================
%!PS-Adobe-2.0 EPSF-1.2
%%Title: AIRFOILS.PS
%%Creator: G SCHRADER
%%CreationDate: 10/12/89
%%Pages: 1
%%BoundingBox:
%%EndComments
%%BeginProlog
/AirfoilDict 150 dict def
AirfoilDict begin
/cl /closepath load def
/ex /exch load def
/gs /gsave load def
/gr /grestore load def
/li /lineto load def
/mo /moveto load def
/rm /rmoveto load def
/np /newpath load def
/rl /rlineto load def
/ro /rotate load def
/sh /show load def
/sc /scale load def
/st /stroke load def
/tr /translate load def
/DrawCoords
{
gs
/lbl ex def
/sca ex def
/yofs ex def
/xofs ex def
/dta ex def
/ymax -100 def
/ymin 100 def
xofs yofs tr
sca dup scale
-90 ro
/chrhgt 0.03125 def
/Helvetica findfont chrhgt scalefont setfont
np
dta 0 get dta 1 get mo
2 2 dta length 1 sub {
dup dta ex get
ex 1 add dta ex get
dup ymax gt { dup /ymax ex def } if
dup ymin lt { dup /ymin ex def } if
li } for
st
0.333 ymax ymin add 2 div mo
lbl dup stringwidth chrhgt add -2 div ex -2 div ex rm sh
90 ro
sca 1 ex div dup scale
xofs neg yofs neg tr
gr
} bind def
end
%%EndProlog
%%BeginSetup
AirfoilDict begin
%%EndSetup
/SD6060 [
1.00000 0.0
0.99661 0.00023
0.98660 0.00108
0.97033 0.00283
0.94829 0.00559
0.92100 0.00941
0.88905 0.01419
0.85301 0.01977
0.81346 0.02595
0.77096 0.03248
0.72602 0.03912
0.67917 0.04563
0.63091 0.05177
0.58174 0.05738
0.53222 0.06225
0.48283 0.06606
0.43386 0.06866
0.38566 0.07003
0.33862 0.07020
0.29316 0.06922
0.24976 0.06715
0.20883 0.06402
0.17076 0.05988
0.13589 0.05480
0.10456 0.04887
0.07700 0.04218
0.05344 0.03486
0.03399 0.02710
0.01879 0.01913
0.00790 0.01132
0.00148 0.00411
0.00025 -0.00159
0.00495 -0.00647
0.01525 -0.01148
0.03068 -0.01612
0.05114 -0.02025
0.07648 -0.02381
0.10645 -0.02678
0.14078 -0.02919
0.17909 -0.03105
0.22096 -0.03238
0.26592 -0.03321
0.31347 -0.03354
0.36306 -0.03338
0.41413 -0.03273
0.46614 -0.03159
0.51852 -0.02995
0.57073 -0.02784
0.62223 -0.02527
0.67254 -0.02231
0.72116 -0.01906
0.76761 -0.01568
0.81133 -0.01236
0.85176 -0.00922
0.88838 -0.00638
0.92070 -0.00399
0.94818 -0.00214
0.97032 -0.00090
0.98661 -0.00024
0.99662 -0.00002
1.00001 -0.00000
] def
/S3021 [
1.00000 0.0
0.99663 0.00039
0.98679 0.00172
0.97104 0.00419
0.94996 0.00769
0.92398 0.01193
0.89336 0.01670
0.85840 0.02198
0.81959 0.02776
0.77748 0.03393
0.73266 0.04038
0.68572 0.04694
0.63730 0.05341
0.58801 0.05954
0.53839 0.06504
0.48891 0.06964
0.43996 0.07312
0.39190 0.07536
0.34513 0.07632
0.29999 0.07596
0.25685 0.07433
0.21611 0.07151
0.17816 0.06753
0.14331 0.06243
0.11182 0.05631
0.08392 0.04930
0.05983 0.04156
0.03968 0.03329
0.02358 0.02472
0.01160 0.01615
0.00374 0.00799
0.00008 0.00099
0.00191 -0.00427
0.00984 -0.00852
0.02320 -0.01232
0.04178 -0.01547
0.06542 -0.01789
0.09395 -0.01957
0.12712 -0.02053
0.16464 -0.02085
0.20614 -0.02059
0.25118 -0.01986
0.29928 -0.01876
0.34988 -0.01742
0.40237 -0.01592
0.45612 -0.01433
0.51047 -0.01273
0.56476 -0.01115
0.61834 -0.00963
0.67056 -0.00821
0.72079 -0.00690
0.76840 -0.00570
0.81283 -0.00462
0.85355 -0.00365
0.89005 -0.00278
0.92187 -0.00193
0.94876 -0.00107
0.97048 -0.00035
0.98660 0.00003
0.99661 0.00006
1.00001 -0.00000
] def
/S4061 [
1.00000 0.0
0.99675 0.00034
0.98709 0.00147
0.97129 0.00363
0.94977 0.00698
0.92304 0.01156
0.89171 0.01729
0.85637 0.02403
0.81765 0.03151
0.77610 0.03945
0.73227 0.04752
0.68665 0.05541
0.63971 0.06283
0.59189 0.06949
0.54359 0.07519
0.49522 0.07974
0.44716 0.08301
0.39979 0.08491
0.35348 0.08542
0.30862 0.08453
0.26554 0.08227
0.22460 0.07876
0.18619 0.07414
0.15074 0.06848
0.11855 0.06186
0.08988 0.05437
0.06493 0.04616
0.04385 0.03741
0.02676 0.02838
0.01380 0.01937
0.00502 0.01069
0.00046 0.00283
0.00079 -0.00320
0.00681 -0.00787
0.01835 -0.01209
0.03499 -0.01545
0.05666 -0.01780
0.08329 -0.01907
0.11475 -0.01932
0.15086 -0.01864
0.19130 -0.01724
0.23566 -0.01527
0.28346 -0.01291
0.33414 -0.01034
0.38708 -0.00771
0.44161 -0.00516
0.49704 -0.00279
0.55267 -0.00069
0.60777 0.00107
0.66164 0.00245
0.71357 0.00342
0.76289 0.00400
0.80895 0.00419
0.85115 0.00405
0.88894 0.00363
0.92184 0.00301
0.94940 0.00225
0.97127 0.00146
0.98714 0.00074
0.99678 0.00020
1.00001 -0.00000
] def
save
72 72 sc % set scale to inches instead of points
%1.000 1.000 1.000 0 0.000 0.000 8.0 10.0 Crop
0 setlinecap
0 setlinejoin
0.001 setlinewidth
%0.000 0.000 0.000 rgb
% Parameters to DrawCoords are ...
% - array of data to use
% - offset from left edge of paper in inches
% - offset from bottom of paper in inches
% - chord in inches
% - label for the airfoil
SD6060 1.5 9.5 9.0 (SD6060) DrawCoords
S3021 3.0 9.5 9.0 (S3021) DrawCoords
S4061 4.5 9.5 9.0 (S4061) DrawCoords
showpage
restore
end
%%Trailer
|
| 1113.10 | FANTASTIC !!! | ROCK::MINER | Electric = No more glow-glop | Thu Oct 12 1989 23:00 | 18 |
| RE: <<< Note 1113.9 by SHTGUN::SCHRADER "CSS::SCHRADER=264-4170=MK01/2K12" >>>
I've been meaning to do this myself but I ain't got a round 'tuit
yet.
It's great to see another PostScript hacker in the notes file.
Thanks for all your contributions. Keep up the good work!!
_____
| \
| \ Silent POWER!
_ ___________ _________ | Happy Landings!
| \ | | | | |
|--------|- SANYO + ]-| ASTRO |--| - Dan Miner
|_/ |___________| |_________| |
| / | " The Earth needs more OZONE,
| / not Caster Oil!! "
|_____/
|
| 1113.11 | | CTD024::TAVARES | John -- Stay low, keep moving | Fri Oct 13 1989 14:06 | 17 |
| HOLY COW, you really did something there! You drew 3, count 'em
three airfoils, with the coordinates occupying at least 20 lines
each (I didn't count them) and your entire program was under 300
lines. You are one hot dog...my fingers are shaking I'm so
excited by this. I've been learning postscript off and on over
the last year just to do this, and you did it in under 300 lines,
and probably with a wave of the hand.
Now tell me, because I want to modify this to draw any airfoil
by entering the coordinates, are those the same ones that came
straight from the offset listing? The reason I ask is that they
don't look like the typical coordinate stations you get with
foils, but Selig is not known for being typical...
Congratulations! Fantastic achievement; this is easily your best
program yet (I found problems with the others when I tried to
generalize them).
|
| 1113.12 | Use tape for a Turbulator | GENRAL::WATTS | | Fri Oct 13 1989 18:08 | 12 |
| I made turbulators using plastic weather stripping tape. The tape I've
used is about 3 or 4 mils thick. I cut it in thin strips and use two or
three layers. It is then placed an inch or so behind the leading edge
on my E205 Pantera. It seems to work, its durable, removeable and
best of all its easy. I think I get the most use out them as a "demon
Teak". Thats one of those things where you are not sure weather it
works or not, but provides a least a psychological advantage over your
competition. If they don't notice that you use them, you can always point
them out and ask how come they don't have any on their plane. Then
state what a BIG difference they made for you. This is most effective just
before they launch.
|
| 1113.13 | twernt nothin... (blush) | SHTGUN::SCHRADER | CSS::SCHRADER=264-4170=MK01/2K12 | Fri Oct 13 1989 20:31 | 24 |
| RE: .11
Gee, thanks for the kind words. The airfoil coordinates came from one of the
previouse notes. I just literally cut and pasted them into the array setups
in the program. The coordinates themselves are just X/Y pairs with X varying
from 0 to 1. X=0 for the wing leading edge and X=1 for the trailing edge.
So, all you have to do to draw a general airfoil (or any old shape for that
matter) is to load an array with X/Y pairs and call DrawCoords with the
appropriate parameters. I've been told that some people specify airfoils
in polar coordinates so to handle this you'd only have to make a DrawPolar
function based on my DrawCoords function. DrawPolar would be about the
same length as DrawCoords but would have to do a couple of extra steps to
get the points back into rectangular coords before drawing the lines.
As it turns out, a fellow a couple of cubes over is a glider freak and sent
off for a copy of Selig's stuff (airfoils and everything). If we can get a
scanner to give us some good text of the coordinates then i'm going to do
a version of this program that will print out ribs of specified size of
whichever of these airfoils you want. This will probably be a while since
he just sent for the stuff.
If I can ever get this together then i'll post it here.
G. Schrader
|
| 1113.14 | tape details. | K::FISHER | Stop and Smell the Balsa! | Mon Oct 16 1989 12:55 | 15 |
| > I made turbulators using plastic weather stripping tape. The tape I've
> used is about 3 or 4 mils thick. I cut it in thin strips and use two or
> three layers. It is then placed an inch or so behind the leading edge
> on my E205 Pantera. It seems to work, its durable, removeable and
Silly question - what exactly does weather stripping tape look like?
I can see myself at K-Mart now trying to get the right stuff and failing.
I may need to tape down some Thermal Sniffler antenna wires and it could double
as a turbulator - sound OK?
Bye --+--
Kay R. Fisher |
---------------O---------------
################################################################################
|
| 1113.15 | Get the Tape at Home Owners Hell | GENRAL::WATTS | | Mon Oct 16 1989 16:56 | 9 |
| Kay: I got the weather stripping tape at our local Home Owner's Hell
store, you know a lumber yard for the do-it yourselfer. Its made by 3M. I
found it in with the weather stripping stuff. It's clear and
comes in 1" and 2" widths (trim it to the width you need). It's designed
for running around the edges of windows to seal air leakes. It also works
well as tape to hold the wings secure to the wing fairings. It seals the
crack between the fuse. and the wing too.
Ron
|
| 1113.16 | Variable airfoils | K::FISHER | Stop and Smell the Balsa! | Wed Oct 18 1989 12:32 | 55 |
| From: henry@ginger.sri.com (Henry A. Pasternack)
Subject: Why variable airfoil.
Date: 16 Oct 89 20:47:27 GMT
Sender: news@unix.SRI.COM
Sailplanes have long (or, more precisely, high aspect ratio) wings
in order to minimize drag due to lift, otherwise known as induced drag
or vortex drag. Induced drag is proportional to the square of the
coefficient of lift; it is the major drag factor in airplanes which
are designed to fly slowly and at high coefficients of lift.
Unfortunately, aircraft flying close to their maximum lift
coefficient are very susceptible to stalls. Even if the pilot is
careful to maintain airspeed above stall speed (very hard to do
precisely in a model), gusts can upset the airflow and induce a
stall. Long-winged planes are especially vulnerable for a number
of reasons: 1) Their wings are more pitch-sensitive than those of lower
aspect-ratio craft; 2) In turns, there is a significant variation of
airspeed from the inboard tip to the outboard one; 3) As a consequence,
it is easy to enter a spin from a stall; 4) The high inertia and roll-
damping of a long wing makes it difficult to level the wings or recover
from a spin quickly.
To compensate for some of these problems, sailplane designers often
add features to their planes to soften their stall characteristics and
to minimize the possibility of spin entry in high angle of attack turns.
An important goal is to minimize the tendency of the tips to stall before
the inboard sections. Since the ailerons are near the tips, a plane
stalling outboard first will lose aileron authority and, hence, roll
control. On the other hand, if the wing stalls inboard first, the nose
will begin to drop before the ailerons are involved, giving the pilot
a warning of impending loss of control.
The flat-bottomed tips of the Eclipse are more highly cambered than
the semi-symmetrical center section. Although they have more drag, they
also have a higher maximum coefficient of lift. In order for this type
of variable airfoil wing to work best, washout should be used to compensate
for the difference in zero-lift angle of attack of the different sections.
Another simple technique for minimizing the tip-stall tendency is to use a
constant-chord wing. This causes the tips to be lightly loaded relative to
their area, so that they fly at a lower lift coefficient than the rest of
the wing.
In general, most techniques which offer theoretical tip-stall
protection also produce theoretical increases in drag. There are some
clever schemes involving careful control over airfoil and washout, but
they are difficult to build accurately. Experienced sailplane
modelers often say that the reality of airflow in the tip region of
model wing is that it is difficult to predict actual versus
theoretical performance. The best advice for winning contests seems
to be to pick a simple design with minimum trickery and learn to fly
it to the limit.
-Henry
|
| 1113.17 | OK here is the fancy smancy com proc | CSC32::M_ANTRY | | Wed Oct 18 1989 20:08 | 212 |
| I have delayed posting this but here goes.
OK George I pirated your program....
OK John you now have a com file to play with.
I took the PS that George came up with it and rolled it into a com proc
similar to the AMA label one that someone rolled up. The com proc asks
for the foil name and the cord and produces a PS file that you can
print. Here it is.
==========================================================================
$ close/nolog infile
$ open/read infile sys$command:
$getfoil:
$ read/prompt= -
"Enter the Airfoil you wish to plot (ex. S3021) <RET> for list: " infile foiln
$ if foiln .nes. "" then goto gotfoil
$ dir/column=4 *.foil
$ goto getfoil
$gotfoil:
$ dir/out=nl: 'f$parse(foiln,".foil")'
$ if $status then goto foilok
$ write sys$output "ERROR - Specified Airfoil not found"
$ goto getfoil
$foilOK:
$ open/read infoil 'f$parse(foiln,".foil")'
$ read/prompt= -
"Enter the Airfoil Cord length (ex. 10.0, 9.5): " infile fsize
$ close/nolog infile
$ if fsize .eqs. "" then fsize = "10.0"
$ !
$ x = f$locate(".",fsize)
$ if x .eq. f$length(fsize)
$ then psout = foiln + fsize + ".ps"
$ else
$ psout = foiln + f$extract(0,x,fsize) + "_"
$ psout = psout + f$extract(x+1,(x+1-f$length(fsize)),fsize) + ".ps"
$ endif
$ copy/nolog sys$input: 'psout'
%!PS-Adobe-2.0 EPSF-1.2
%%Title: AIRFOILS.PS
%%Creator: G SCHRADER
%%CreationDate: 10/12/89
%%Pages: 1
%%BoundingBox:
%%EndComments
%%BeginProlog
/AirfoilDict 150 dict def
AirfoilDict begin
/cl /closepath load def
/ex /exch load def
/gs /gsave load def
/gr /grestore load def
/li /lineto load def
/mo /moveto load def
/rm /rmoveto load def
/np /newpath load def
/rl /rlineto load def
/ro /rotate load def
/sh /show load def
/sc /scale load def
/st /stroke load def
/tr /translate load def
/DrawCoords
{
gs
/lbl ex def
/sca ex def
/yofs ex def
/xofs ex def
/dta ex def
/ymax -100 def
/ymin 100 def
xofs yofs tr
sca dup scale
-90 ro
/chrhgt 0.03125 def
/Helvetica findfont chrhgt scalefont setfont
np
dta 0 get dta 1 get mo
2 2 dta length 1 sub {
dup dta ex get
ex 1 add dta ex get
dup ymax gt { dup /ymax ex def } if
dup ymin lt { dup /ymin ex def } if
li } for
st
0.333 ymax ymin add 2 div mo
lbl dup stringwidth chrhgt add -2 div ex -2 div ex rm sh
90 ro
sca 1 ex div dup scale
xofs neg yofs neg tr
gr
} bind def
end
%%EndProlog
%%BeginSetup
AirfoilDict begin
%%EndSetup
$ open/append outfile 'psout'
$ write outfile "/''foiln' ["
$dataloop:
$ read/end_of_file=dataeof infoil inline
$ write outfile inline
$ goto dataloop
$dataeof:
$ close/nolog infoil
$ write outfile " ] def"
$ close/nolog outfile
$ append sys$input 'psout'
save
72 72 sc % set scale to inches instead of points
%1.000 1.000 1.000 0 0.000 0.000 8.0 10.0 Crop
0 setlinecap
0 setlinejoin
0.001 setlinewidth
%0.000 0.000 0.000 rgb
% Parameters to DrawCoords are ...
% - array of data to use
% - offset from left edge of paper in inches
% - offset from bottom of paper in inches
% - chord in inches
% - label for the airfoil
$ open/append outfile 'psout'
$ write outfile "''foiln' 3.0 10.5 ''fsize' (''foiln' @ ''fsize'"") DrawCoords"
$ write outfile "''foiln' 6.0 10.5 ''fsize' (''foiln' @ ''fsize'"") DrawCoords"
$ close/nolog outfile
$!
$ append sys$input 'psout'
showpage
restore
end
%%Trailer
$ exit
=============================================================================
Here is the 3021 file that George had in file format named S3021.FOIL
1.00000 0.0
0.99663 0.00039
0.98679 0.00172
0.97104 0.00419
0.94996 0.00769
0.92398 0.01193
0.89336 0.01670
0.85840 0.02198
0.81959 0.02776
0.77748 0.03393
0.73266 0.04038
0.68572 0.04694
0.63730 0.05341
0.58801 0.05954
0.53839 0.06504
0.48891 0.06964
0.43996 0.07312
0.39190 0.07536
0.34513 0.07632
0.29999 0.07596
0.25685 0.07433
0.21611 0.07151
0.17816 0.06753
0.14331 0.06243
0.11182 0.05631
0.08392 0.04930
0.05983 0.04156
0.03968 0.03329
0.02358 0.02472
0.01160 0.01615
0.00374 0.00799
0.00008 0.00099
0.00191 -0.00427
0.00984 -0.00852
0.02320 -0.01232
0.04178 -0.01547
0.06542 -0.01789
0.09395 -0.01957
0.12712 -0.02053
0.16464 -0.02085
0.20614 -0.02059
0.25118 -0.01986
0.29928 -0.01876
0.34988 -0.01742
0.40237 -0.01592
0.45612 -0.01433
0.51047 -0.01273
0.56476 -0.01115
0.61834 -0.00963
0.67056 -0.00821
0.72079 -0.00690
0.76840 -0.00570
0.81283 -0.00462
0.85355 -0.00365
0.89005 -0.00278
0.92187 -0.00193
0.94876 -0.00107
0.97048 -0.00035
0.98660 0.00003
0.99661 0.00006
1.00001 -0.00000
|
| 1113.18 | My RG12A looks like a zz8767jdy | CSC32::M_ANTRY | | Wed Oct 18 1989 20:12 | 74 |
| Ok now here is a problem I am having!!!
I tried to plot a RG12A airfoil using info I got from SOARTECH and it
plots OK but the leading edge is all screwy. George, could you take a
look at what is wrong? I also have a smaller file that is for a STAB
and is a NACA63009 but it only contains 25 sets of point as apposed to
the standard 61...any comments on that.
Here is the RG12A but I dont think it is correct...
1.00000 0.000
0.99665 0.00059
0.98703 0.00246
0.97194 0.00551
0.95179 0.00921
0.92666 0.01325
0.89678 0.01766
0.86258 0.02238
0.82453 0.02731
0.78310 0.03232
0.73879 0.03730
0.69213 0.04212
0.64368 0.04674
0.59393 0.05104
0.54340 0.05487
0.49264 0.05809
0.44217 0.06058
0.39250 0.06222
0.34413 0.06294
0.29752 0.06267
0.25311 0.06138
0.21131 0.05906
0.17248 0.05573
0.13697 0.05143
0.10506 0.04625
0.7702 0.04030
0.5306 0.03373
0.3339 0.02671
0.1810 0.01942
0.0735 0.01226
0.0100 0.00531
0.00 0.000
0.0354 -0.00389
0.0953 -0.00703
0.2204 -0.01138
0.3760 -0.01484
0.5756 -0.01793
0.8143 -0.02053
0.10918 -0.02266
0.14059 -0.02434
0.17548 -0.02560
0.21358 -0.02646
0.25462 -0.02696
0.29829 -0.02711
0.34421 -0.02694
0.39199 -0.02647
0.44119 -0.02569
0.49132 -0.02461
0.54192 -0.02318
0.59248 -0.02135
0.64260 -0.01890
0.69148 -0.01559
0.73816 -0.01184
0.78233 -0.00827
0.82366 -0.00517
0.86166 -0.00266
0.89589 -0.00084
0.92587 0.00030
0.95113 0.00085
0.97147 0.00092
0.98682 0.00064
0.99661 0.00022
0.10000 0.00000
|
| 1113.19 | Better late than never | LEDS::COHEN | Some limitations may apply... | Wed Oct 18 1989 21:05 | 36 |
| Re. .9, what do turbulators look like, where do they go, etc....
essentially, a turbulator looks like this...
________________________________________________________ <- leading edge
|/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\| <- Turbulator
| |
| TOP OF WING |
| |
| |
| |
-------------------------------------------------------- <- trailing edge
Made from some 1/32 balsa, or a few layers of tape. The idea is to get
the induced turbulence to occur as close to the leading edge as
possible. You want it like that so that the air flow has the
opportunity to establish a turbulent boundary layer along the surface of
the wing as early as possible (otherwise, the induced drag near the
trailing edge becomes excessive). You don't want the turbulator to
induce turbulence along the bottom of the wing, though, so be sure that
anything you add to cuase turbulence is BEHIND the front of the leading
edge. Don't go back more than, say, 2 or 3 mm back, though, and
remember, you don't want something that creates a BIG amount of
turbulence, you only want a thinthinthin layer of turbulent air flowing
across the top of the wing.
The turbulator doesn't have to be serrated, though. A thin piece of
wire (like 20 or 22 guage) glued along, but just behind, the leading
edge will work quite well. I've seen people use a piece of 1/16 square
balsa stringer, sanded down, too.
Re. -.1, wings stalling...
Elliptical wings have the unique property in that they stall uniformily,
across the entire wing, root to tip, at their minumum airspeed.
|
| 1113.20 | Variable Airfoils (continued) | K::FISHER | Stop and Smell the Balsa! | Thu Oct 19 1989 11:42 | 55 |
| From: henry@ginger.sri.com (Henry A. Pasternack)
Subject: Why variable airfoil.
Date: 16 Oct 89 20:47:27 GMT
Sender: news@unix.SRI.COM
Sailplanes have long (or, more precisely, high aspect ratio) wings
in order to minimize drag due to lift, otherwise known as induced drag
or vortex drag. Induced drag is proportional to the square of the
coefficient of lift; it is the major drag factor in airplanes which
are designed to fly slowly and at high coefficients of lift.
Unfortunately, aircraft flying close to their maximum lift
coefficient are very susceptible to stalls. Even if the pilot is
careful to maintain airspeed above stall speed (very hard to do
precisely in a model), gusts can upset the airflow and induce a
stall. Long-winged planes are especially vulnerable for a number
of reasons: 1) Their wings are more pitch-sensitive than those of lower
aspect-ratio craft; 2) In turns, there is a significant variation of
airspeed from the inboard tip to the outboard one; 3) As a consequence,
it is easy to enter a spin from a stall; 4) The high inertia and roll-
damping of a long wing makes it difficult to level the wings or recover
from a spin quickly.
To compensate for some of these problems, sailplane designers often
add features to their planes to soften their stall characteristics and
to minimize the possibility of spin entry in high angle of attack turns.
An important goal is to minimize the tendency of the tips to stall before
the inboard sections. Since the ailerons are near the tips, a plane
stalling outboard first will lose aileron authority and, hence, roll
control. On the other hand, if the wing stalls inboard first, the nose
will begin to drop before the ailerons are involved, giving the pilot
a warning of impending loss of control.
The flat-bottomed tips of the Eclipse are more highly cambered than
the semi-symmetrical center section. Although they have more drag, they
also have a higher maximum coefficient of lift. In order for this type
of variable airfoil wing to work best, washout should be used to compensate
for the difference in zero-lift angle of attack of the different sections.
Another simple technique for minimizing the tip-stall tendency is to use a
constant-chord wing. This causes the tips to be lightly loaded relative to
their area, so that they fly at a lower lift coefficient than the rest of
the wing.
In general, most techniques which offer theoretical tip-stall
protection also produce theoretical increases in drag. There are some
clever schemes involving careful control over airfoil and washout, but
they are difficult to build accurately. Experienced sailplane
modelers often say that the reality of airflow in the tip region of
model wing is that it is difficult to predict actual versus
theoretical performance. The best advice for winning contests seems
to be to pick a simple design with minimum trickery and learn to fly
it to the limit.
-Henry
|
| 1113.21 | Now its user-friendly | CTD024::TAVARES | John -- Stay low, keep moving | Thu Oct 19 1989 13:29 | 38 |
| Great job Mark! It looks like you put the coordinates in a file
named Foilname.foil????, then read it through your interface????
As soon as this war's over I'll try it, maybe sometime late next
week.
On the foil problem. I think you have to change the number of
times the loop goes to match the number of coordinates that you
have. This is less than delicate surgery for a postscript guru,
and a little more complicated for scrap yard welders like me.
I think the way to make George's program generalized is to have
places at the top to enter the number of coordinates, the size
of the foil, etc; in other words declare these as variables.
Which is why I was asking how the coordinates were entered; to
help me figure out how the loop works. I haven't gotten back to
it yet.
Anyway, then you can enter the stuff directly into the ps file --
though Mark's interface is pretty snazzy.
Now for a real go-fast, it should also mark the chord line, then
put numbered vertical lines at the coordinate points so you can
just paste it on the end templates for foam cutting. Of course,
we need a left and right...
I may live to regret this, but I do have a sizable collection of
airfoil coordinates, both RC and freeflight. I subscribe to
Model Builder and keep the coordinates they publish plus I have
some from some general reference books. So, if you're looking for
one let me know.
BTW -- I did figure out a slick way to get the left and right
templates conventionally. Draw/trace the foil on vellum and mark
in the lines. Then take it to the copy machine and photo it
wrong side down. Presto, a nice backwards foil. Of course, as
the one calling the numbers, I feel obligated to use the
backwards side, while the disinterested volunteer gets the good
numbers.
|
| 1113.22 | More low tech copier tricks... | TEKTRM::REITH | Jim Reith DTN 235-8459 HANNAH::REITH | Thu Oct 19 1989 14:29 | 3 |
| Copy/print it on an overhead slide and with a piece of white paper as backing,
you can copy it from either side. (overheads make nice painting stencils after
being cut with an xacto knife)
|
| 1113.24 | More airfoil coordinates | BARNA::JORDI | | Fri Oct 20 1989 08:42 | 184 |
| RE: .11
Hi,
Congratulations for the fantastic postcript program.
I don't know nothing about postcript programation but I've tried to run
it with the Wortmann FX 61-163 and S4180-098-84 airfoil coordinates and
it works very well !!
The coordinates came from the Martin Simons's book "Model Aircraft
Aerodinamics" and from "Radio Control Models & Electronics" magazine.
FX61-163
1.00000 0.00000
0.99891 0.00069
0.99571 0.00206
0.99034 0.00390
0.98291 0.00610
0.97344 0.00875
0.96192 0.01167
0.94848 0.01481
0.93299 0.01817
0.91571 0.02176
0.89644 0.02560
0.87590 0.02968
0.85350 0.03403
0.82970 0.03861
0.80435 0.04347
0.77773 0.04856
0.74995 0.05388
0.72115 0.05935
0.69133 0.06497
0.66074 0.07064
0.62938 0.07637
0.59750 0.08208
0.56525 0.08772
0.53274 0.09303
0.49997 0.09780
0.46733 0.10168
0.43469 0.10457
0.40243 0.10639
0.37056 0.10728
0.33933 0.10723
0.30861 0.10635
0.27891 0.10455
0.24998 0.10194
0.22221 0.09844
0.19558 0.09422
0.17037 0.08924
0.14643 0.08371
0.12403 0.07760
0.10330 0.07109
0.08422 0.06412
0.06694 0.05687
0.05158 0.04929
0.03802 0.04175
0.02650 0.03402
0.01702 0.02641
0.00960 0.01925
0.00422 0.01234
0.00102 0.00566
0.00102 -0.00248
0.00422 -0.00560
0.00960 -0.00907
0.01702 -0.01272
0.02650 -0.01656
0.03802 -0.02027
0.05158 -0.02412
0.06694 -0.02786
0.08422 -0.03160
0.10330 -0.03518
0.12403 -0.03870
0.14643 -0.04199
0.17037 -0.04511
0.19558 -0.04792
0.22221 -0.05044
0.24998 -0.05252
0.27891 -0.05421
0.30861 -0.05537
0.33933 -0.05609
0.37056 -0.05625
0.40243 -0.05585
0.43469 -0.05474
0.46733 -0.05293
0.49997 -0.05039
0.53274 -0.04719
0.56525 -0.04324
0.59750 -0.03845
0.62938 -0.03288
0.66074 -0.02635
0.69133 -0.02079
0.72115 -0.01517
0.74995 -0.01014
0.77773 -0.00576
0.80435 -0.00201
0.82970 0.00110
0.85350 0.00358
0.87590 0.00542
0.89644 0.00667
0.91571 0.00743
0.93299 0.00749
0.94848 0.00715
0.96192 0.00637
0.97344 0.00526
0.98291 0.00392
0.99034 0.00273
0.99571 0.00150
0.99891 0.00044
1.00001 0.00000
S4180-098-84
1.00000 0.00000
0.99684 0.00036
0.98746 0.00156
0.97208 0.00376
0.95106 0.00702
0.92483 0.01132
0.89384 0.01661
0.85861 0.02279
0.81971 0.02971
0.77768 0.03718
0.73313 0.04497
0.68661 0.05280
0.63859 0.06042
0.58961 0.06762
0.54019 0.07420
0.49083 0.07997
0.44204 0.08472
0.39427 0.08829
0.34798 0.09050
0.30355 0.09118
0.26126 0.09018
0.22127 0.08751
0.18383 0.08329
0.14916 0.07770
0.11757 0.07095
0.08935 0.06323
0.06476 0.05468
0.04398 0.04553
0.02726 0.03596
0.01467 0.02606
0.00607 0.01606
0.00129 0.00643
0.00016 -0.00200
0.00377 -0.00814
0.01306 -0.01234
0.02779 -0.01523
0.04791 -0.01670
0.07351 -0.01680
0.10453 -0.01564
0.14065 -0.01417
0.18140 -0.01202
0.22624 -0.00957
0.27459 -0.00696
0.32585 -0.00433
0.37936 -0.00178
0.43445 0.00060
0.49043 0.00273
0.54656 0.00455
0.60221 0.00601
0.65660 0.00708
0.70908 0.00774
0.75697 0.00800
0.80564 0.00786
0.84847 0.00735
0.88692 0.00652
0.92046 0.00540
0.94862 0.00407
0.97093 0.00262
0.98703 0.00131
0.99674 0.00035
1.00001 0.00000
Ii is a hard work to type coordinates !!!
Regards.
Jordi
|
| 1113.25 | great stuff ! | 41055::CULLEN | think twice, ... cut once ! | Fri Oct 20 1989 12:29 | 10 |
|
Hello,
Again congratulations for the fantastic postcript program. Now I must
try and dig out some airfoils... build up a library of them here.
Regards,
Eric();
|
| 1113.26 | More on variable camber | K::FISHER | Stop and Smell the Balsa! | Fri Oct 20 1989 17:50 | 74 |
| From: henry@ginger.sri.com (Henry A. Pasternack)
Subject: More on variable camber.
Date: 19 Oct 89 19:24:05 GMT
Sender: news@unix.SRI.COM
Wayne says:
>From all I have read, the best approach is to use a lower-camber
>(more symmetrical) and thicker airfoil at the tips. This allows
>you to avoid tip stall without washout.
>
>I have to plug Martin Simons' book "Model Aircraft Aerodynamics"
>yet again. I found it very helpful. It is available from Zenith
>(see their ad in any model magazine.)
I would like to quote Simons on this exact subject:
"By varying the camber along the span, the stalling characteristics
may be controlled. If the camber is reduced towards the tips, with no
geometric twist (i.e. the true chord line of each rib is at the same
angle to the building board or datum line), the wing will have an
*aerodynamic* washout because the *aerodynamic* zero angle of attack at
each point will differ. Assuming a nearly elliptical platform, the wing
roots, because of the greater camber there, will reach their stalling
speed *before* the tips. This is good in the sense that it prevents
tip stalling. At high speeds, however, when the roots are still lifting,
the tips will already be close to their aerodynamic zero. The lift
distribution will not be elliptical, and at some speed the tips will begin
to bend downwards like a wing with marked geometrical washout. To restore
elliptical lift distribution, the tips should really by twisted the
other way (wash-in), which will unfortunately cause tip stalling because
the less-cambered profile has a lower cl maximum. Many models have been
built with reduced camber at the tips *plus* a few degrees of washout.
This combines both aerodynamic and geometric washout; the total effect
may be as much as six or seven degrees of aerodynamic twist. The tip
stall is controlled, but efficiency suffers.
If, instead of camber decreasing at the tips, it is increased, or
decreased at the roots, the tips will tend to stall first, which is
highly undesirable. However, if the aerodynamic twist or 'wash-in'
caused by the increased tip camber is counteracted by an equal
geometric twist or washout in the opposite direction, the result is
excellent. If, for example, the difference in absolute zero of the
aerofoil at the wing root and that at the tip is two degrees, with the
more cambered form at the tip the geometric twist should be two
degrees washout or, to be on the safe side, a little more. The whole
wing then reaches its aerodynamic zero at the same angle, and the cl
from tip to root is nearly constant. The lift load thus approaches as
closely as possible to the ideal (assuming the platform of the wing is
a good approximation to an ellipse). There is no tip stall, because
the more cambered profile has a higher cl max., and, measured from the
*aerodynamic zero*, stalls later. Hence, the root reaches the
stalling angle first. The wing is efficient over a wide range of
speeds. This technique is widely used by designers of full-sized
sailplanes and may be applied to models in exactly the same way. In
design it is essential to know the zero-lift angle for the profiles
used. This may be obtained from the wind tunnel results if available.
In some cases the figures are given with the aerofoil ordinates. Wind
tunnel results do not always confirm the computed figures. On the
building board it is of course very important to lay out such a wing
accurately. The ribs may be cut by the sandwich method between templates
of the appropriate aerofoils at tip and root, or the section may be
constant to the semi- or two-thirds span position and changed progressively
from there to the tip. Cutting foam plastic wings is equally straight-
forward. On assembly, careful work should ensure that the angle of each
rib is correct relative to its designed chord line. A casual chocking
up of the trailing edge to some angle or other is not good enough."
One comment: Take all of this with a grain of salt. What is ideal in
theory may not be so in practice. There are many factors which conspire
to upset theoretical performance in a practical model.
-Henry
|
| 1113.27 | First try at the airfoil program | CTD024::TAVARES | John -- Stay low, keep moving | Tue Oct 24 1989 15:36 | 177 |
| Here is the first step with modifying the airfoil program. I
changed it to print a single airfoil, the CLARK Y with the
coordinates more frequently given in books.
Note that I had to add several coordinates; the first given data
point is at .125 inch. This puts a straight line between there
and 0.0, so I stood over the printer and fudged in coordinates
until it came out to a fair curve. It still could use another
one or two. This is why the Selig foils had so many coordinates
-- they were made for computer repro, whereas the ordinarily
published ones are for drawing with a french curve. Anyway, if
you want to use it, expect to fool arouund a bit with the nose
radius.
Anyone with more math than I who can supply a function for
interpolating those missing data points? I'll bet its a piece of
cake with a calculator, but its way beyond me.
I redefined the size of the dictionary (an array). I think that
any size larger than the number of data points you have will
work; before I'm done I'll probably make it something like 60.
If you want to experiment with it, enter the coordinates in the
right column for the data points given in your listing. You can
add extra points from your listing as long as you move over the
percent/offset decimal places to read in hundreths-- these may be
seen as something like 10.00/9.6000 in your listing; simply move
the decimal point over two places to make it .10/.0960 and you've
got it.
After entering coordinates go to the section *Parameters to
DrawCoords* and enter the offsets to the page. Place the paper in
landscape; that is, turned 90 deg from the way a page of text is
usually printed, and measure the position. The left edge offset
positions the nose of the foil, the bottom edge offset is along
the zero line of the foil coordinates.
This is the first try; I thought someone may like to tinker a bit
with it. It will print a very usable airfoil for foam cutting.
Now I get out the cutting torch and really hack it up!
%!PS-Adobe-2.0 EPSF-1.2
%%Title: AIRFOILS.PS
%%Creator: G SCHRADER
%%CreationDate: 10/12/89
%%Pages: 1
%%BoundingBox:
%%EndComments
%%BeginProlog
/AirfoilDict 35 dict def
AirfoilDict begin
/cl /closepath load def
/ex /exch load def
/gs /gsave load def
/gr /grestore load def
/li /lineto load def
/mo /moveto load def
/rm /rmoveto load def
/np /newpath load def
/rl /rlineto load def
/ro /rotate load def
/sh /show load def
/sc /scale load def
/st /stroke load def
/tr /translate load def
/DrawCoords
{
gs
/lbl ex def
/sca ex def
/yofs ex def
/xofs ex def
/dta ex def
/ymax -100 def
/ymin 100 def
xofs yofs tr
sca dup scale
-90 ro
/chrhgt 0.05 def
/Helvetica findfont chrhgt scalefont setfont
np
dta 0 get dta 1 get mo
2 2 dta length 1 sub {
dup dta ex get
ex 1 add dta ex get
dup ymax gt { dup /ymax ex def } if
dup ymin lt { dup /ymin ex def } if
li } for
st
0.333 ymax ymin add 2 div mo
lbl dup stringwidth chrhgt add -2 div ex -2 div ex rm sh
90 ro
sca 1 ex div dup scale
xofs neg yofs neg tr
gr
} bind def
end
%%EndProlog
%%BeginSetup
AirfoilDict begin
%%EndSetup
/clarky [
%topside
1.00 0.0012000
0.95 0.0149000
0.90 0.0280000
0.80 0.0522000
0.70 0.0735000
0.60 0.0915000
0.50 0.1052000
0.40 0.1140000
0.30 0.1170000
0.20 0.1136000
0.15 0.1068000
0.10 0.0960000
0.075 0.0885000
0.050 0.0790000
0.025 0.0650000
0.0125 0.0545000
0.0062 0.0475000 %I added this
0.0031 0.0420000 %ditto
0.0000 0.0350000
%underside
0.0000 0.0350000
0.0015 0.0290000 %ditto
0.0031 0.0275000 %ditto
0.0062 0.0240000 %ditto
0.0125 0.0193000
0.025 0.0147000
0.050 0.0093000
0.075 0.0063000
0.10 0.0042000
0.15 0.0015000
0.20 0.0003000
0.30 0.0000000
0.40 0.0000000
0.50 0.0000000
0.60 0.0000000
0.70 0.0000000
0.80 0.0000000
0.90 0.0000000
0.95 0.0000000
1.00 0.0000000
] def
save
72 72 sc % set scale to inches instead of points
%1.000 1.000 1.000 0 0.000 0.000 8.0 10.0 Crop
0 setlinecap
0 setlinejoin
0.001 setlinewidth
%0.000 0.000 0.000 rgb
% Parameters to DrawCoords are ...
% - array of data to use
% - offset from left edge of paper in inches
% - offset from bottom of paper in inches
% - chord in inches
% - label for the airfoil
%Sample: SD6060 1.5 9.5 9.0 (SD6060) DrawCoords
clarky 4.25 10.0 9.0 (clarky) DrawCoords
showpage
restore
end
%%Trailer
|
| 1113.28 | French curve = Cubic spline algorithm | TEKTRM::REITH | Jim Reith DTN 235-8459 HANNAH::REITH | Tue Oct 24 1989 15:45 | 4 |
| Sounds like what you want, John, is a cubic spline function which (like a french
curve) will draw a smooth curve through any three points. It's a built-in
function in X Windows and TEKtronix so I would imagine it's in Postscript too.
(calling all gurus ;^)
|
| 1113.29 | | CTD024::TAVARES | John -- Stay low, keep moving | Tue Oct 24 1989 20:40 | 19 |
| Well, actually the postscript program that George wrote does a
pretty good job of connecting the points into a smooth curve.
Especially when you use all the data points given for the Selig
airfoils. The problem is that most foil listings start at 000,
then the next coordinate is at 1.25% (.0125) -- this creates a
straight line between this point an 000.
I know that Winfain (boy ain't I a snob, dropping free flighter
names in here), says that you should have a straight flat surface
at the nose of the foil, but this isn't what we want here.
So we have to interpolate the data points between 000 and 1.25%
-- I chose .064 and .031 for convenience, and I hacked the curve
until it was right. What I was looking for is a way to do this
with less hacking, though I suspect that this is the easiest way.
I also did this later with the Eppler 374 foil, a nice
semi-symetrical one. It looks great, though it needs more work
at the nose.
|
| 1113.30 | The STAB of the week club | CSC32::M_ANTRY | | Tue Oct 31 1989 02:25 | 9 |
| I just cut some NACA63009 Stabs that were 5" root and 4" tips that were
12" wide. This airfoil is a symetrical Airfoil similiar to the NACA009
but with the max thickness moved back further from the leading edge.
What that really does? dont know supposed to be the airfoil of the week
for STABS. These would really look good on a Pantera or a Sagitta.
Anyone interested in a set let me know.
Also I am going to try to send some samples and video to the next
DECRCM meeting but might not make it in time for the Nov. meeting.
|
| 1113.31 | Airfoil numbers | K::FISHER | Stop and Smell the Balsa! | Mon Nov 06 1989 12:40 | 41 |
| From: henry@ginger.sri.com (Henry A. Pasternack)
Subject: Airfoil parameters.
Date: 3 Nov 89 23:38:03 GMT
Sender: news@unix.SRI.COM
Bill Frolik asks:
> <What do these numbers mean?>
>
>
> S4110-084-84 (Is this airfoil ID arbitrary, or
> do the numbers convey information
> about the airfoil?)
>
> d = 8.38
> xd = 27.70
> f = 3.13
> xf = 46.80
> a0(inf) = -3.679 (that's "alpha-zero-infinity")
> cm0 = -0.0953
I believe the last two numbers in the Selig designation are the
serial number and the date, i.e., airfoil 84 of 1984. I don't know
the significance of the first four digits; maybe Michael could tell
you.
Alpha-zero is the geometric angle of attack at which an infintely
long wing of this profile would generate zero lift. That is, the
wing must be angled down 3.679 degrees to achieve zero lift.
Cm0 is the coefficient of moment of the airfoil at zero lift. It
quantifies the extent to which the airfoil pitches up or down at the
zero lift angle of attack. This is important because it has a bearing
on the pitch stability of the plane and the size requirements for the
stabilizer.
I believe "d", "xd", "f", and "xf" refer to the thickness and camber
of the airfoil: 8.38% maximum thickness at 27.7% chord and 3.13% maximum
camber at 46.8% chord.
-Henry
|
| 1113.32 | Eppler 193 Information | USRCV1::BLUMJ | | Thu Nov 16 1989 11:21 | 7 |
| Can anyone tell me the flight characteristics of the Eppler 193
airfoil? If you have a sailplane with this airfoil I would be
curious to know how it flew/flies.
Thanks,
Jim
|
| 1113.33 | Eppler 197, NACA 2415 | CTD024::TAVARES | Stay Low, Keep Moving | Tue Jan 23 1990 19:02 | 123 |
| Since posting .27 I have been a busy little bugger entering
coordinates and generating airfoils. Here are a couple more that
have been successful. The problem with having to fudge in nose
coordinates still persists, but the following ones are good
enough to make templates out of with a little sandpaper work...
Enjoy!
%Eppler 197
/airfoil [
%topside
1.00 0.00000
0.99642 0.00050
0.98604 0.00219
0.96960 0.00530
0.94778 0.00960
0.92096 0.01478
0.88939 0.02068
0.85349 0.02733
0.81384 0.03466
0.77105 0.04254
0.72575 0.05079
0.67860 0.05920
0.63028 0.06752
0.58146 0.07542
0.53282 0.08246
0.48474 0.08806
0.43735 0.09191
0.39085 0.09394
0.34551 0.09413
0.30159 0.09250
0.25933 0.08918
0.21902 0.08442
0.18112 0.07844
0.14599 0.07139
0.11402 0.06345
0.08551 0.05478
0.06075 0.04556
0.03996 0.03600
0.02335 0.02633
0.01104 0.01683
0.00318 0.00789
0.00000 0.00000
%underside
0.00000 -0.00200
0.00279 -0.00640
0.01164 -0.01278
0.02555 -0.01983
0.04438 -0.02454
0.06797 -0.02945
0.09610 -0.03365
0.12852 -0.03706
0.16493 -0.03955
0.20495 -0.04125
0.24818 -0.04195
0.29414 -0.04185
0.34231 -0.04085
0.39236 -0.03855
0.44415 -0.03535
0.49723 -0.03165
0.55091 -0.02765
0.60447 -0.02365
0.65718 -0.01965
0.70834 -0.01595
0.75725 -0.01266
0.80323 -0.00965
0.84564 -0.00715
0.88388 -0.00505
0.91738 -0.00325
0.94572 -0.00185
0.96864 -0.00075
0.98572 -0.00009
0.99637 -0.00005
1.00000 0.00000
] def
%%NACA_2415
/airfoil [
%topside
1.00 0.00016
0.9500 0.0134
0.900 0.0245
0.800 0.0441
0.700 0.0610
0.600 0.0750
0.500 0.0857
0.400 0.0925
0.300 0.0938
0.250 0.0917
0.200 0.0870
0.150 0.0797
0.100 0.0683
0.075 0.0606
0.050 0.0507
0.025 0.0371
0.0125 0.0271 %1/8 inch
0.0062 0.0185 %1/16 inch
0.0031 0.0125 %1/32 inch
0.0015 0.0070 %1/64 inch
0.000 0.0000
%underside
0.00000 0.0000
0.0031 -0.0100 %1/32
0.0062 -0.0140 %1/16
0.0125 -0.0206 %1/18
0.0250 -0.0286
0.0500 -0.0384
0.0750 -0.0447
0.1000 -0.0490
0.1500 -0.0542
0.2000 -0.0566
0.2500 -0.0570
0.3000 -0.0562
0.400 -0.0525
0.500 -0.0467
0.600 -0.0390
0.700 -0.0305
0.800 -0.0215
0.900 -0.0117
0.950 -0.0068
1.000 0.00016
] def
|
| 1113.34 | E214, SD7003, and fluff | K::FISHER | Only 37 Days till Phoenix! | Mon Feb 05 1990 13:35 | 264 |
| This just in from the UUCP net.
Bye --+--
Kay R. Fisher |
---------------O---------------
################################################################################
From: ms2@psuecl.bitnet
Subject: Re: need coords for E214
Date: 2 Feb 90 17:10:48 GMT
Here are coordinates for the E214.
Profil 214 Dicke 11.1%
1.00000 0.00000
0.99669 0.00104
0.98737 0.00422
0.97312 0.00916
0.95431 0.01501
0.93081 0.02139
0.90279 0.02833
0.87072 0.03576
0.83508 0.04344
0.79626 0.05105
0.75457 0.05841
0.71040 0.06544
0.66430 0.07207
0.61682 0.07813
0.56852 0.08344
0.51991 0.08776
0.47142 0.09093
0.42346 0.09281
0.37645 0.09332
0.33076 0.09241
0.28674 0.09008
0.24474 0.08639
0.20510 0.08142
0.16816 0.07532
0.13424 0.06822
0.10365 0.06028
0.07665 0.05168
0.05349 0.04258
0.03434 0.03321
0.01934 0.02379
0.00856 0.01465
0.00210 0.00619
0.00005 -0.00086
0.00360 -0.00632
0.01326 -0.01087
0.02830 -0.01475
0.04858 -0.01784
0.07390 -0.02011
0.10406 -0.02161
0.13874 -0.02236
0.17759 -0.02245
0.22017 -0.02193
0.26599 -0.02086
0.31449 -0.01928
0.36508 -0.01721
0.41714 -0.01453
0.47030 -0.01100
0.52450 -0.00678
0.57932 -0.00245
0.63400 0.00155
0.68770 0.00495
0.73959 0.00756
0.78883 0.00923
0.83461 0.00994
0.87612 0.00970
0.91265 0.00862
0.94352 0.00684
0.96809 0.00461
0.98582 0.00235
0.99646 0.00065
1.00000 0.00000
Michael Selig
Penn State, Dept. of Aerospace Eng.
233 Hammond Bldg.
University Park, PA 16802
e-mail: ms2@psuecl.bitnet
From: ms2@psuecl.bitnet
Subject: Re: Airfoil suggestions?
Date: 2 Feb 90 18:56:38 GMT
In article <4484@orion.cf.uci.edu> mnelson@vmsa.oac.uci.edu writes:
>I am going to start designing/building a small (50-60 in), lightweight
>(10-15 oz), polyhedral, arrow-shaft tail boom thermal/slope glider.
>Does anybody have any suggestions for a good airfoil for such a craft?
At this low total weight, you need an airfoil that works well at relatively
low Reynolds numbers. I would suggest a new airfoil that you probably
have not heard of: the SD7003 designed by John Donovan and me. We
tested several airfoils (including the SD7003) in a wind tunnel and
have made the data available through Soartech 8: AIRFOILS AT LOW SPEEDS.
The report/book is 400+ pages long with about 100 pages of written text.
There are not any specific suggestions made as to which airfoil one should
use for a given aircraft. This is left as a problem for the reader.
You will have to study the polars and read a little about aerodynamics
in order to wisely apply the data to your specific aircraft.
I have included a blurb below. (I have posted this before and probably will
again.) I have listed the coordinates to the SD7003.
Good luck.
*******************************************************************************
* AIRFOILS AT LOW SPEEDS by Michael Selig, John Donovan, and David Fraser
-- A special edition of Soartech published by Herk Stokely
through the non-profit initiative of the Tidewater Model Soaring Society.
* Soartech 8 is available from: Herk Stokely
1504 N. Horseshoe Circle
Virginia Beach, VA 23451
* Over 60 wind tunnel models tested at Princeton University
* Over 130 polars generated
* 54 different airfoils tested as listed below
* 400 pages of text, data plots, graphs,
tabulated performance data and airfoil coordinates
* Reynolds numbers tested: 60k, 100k, 150k, 200k, 300k
* $15 continental USA & Canada, $20 overseas surface, $30 overseas air.
* Airfoils tested: AQUILA FX63-137 S3014 SD7037
CLARK-Y HQ2/9 S3016 SD7043
DAE51 J5012 S3021 SD7062
DF101 M06-13-128 S4061 SD7080
DF102 MB253515 S4062 SD7084
DF103 NACA 0009 S4180 SD7090
E193 NACA 2.5411 S4233 SD8000
E193MOD NACA 64A010 SD2030 SD8020
E205 NACA 6409 SD2083 SD8040
E214 RG15 SD5060 SPICA
E374 S2048 SD6060 WB135/35
E387 S2055 SD6080 WB140/35/FB
FLAT PLATE S2091 SD7003
FX60-100 S3010 SD7032
* Excerpted from the book:
The history of this experimental program on low-speed airfoils is
extensive. In August 1986, work toward testing model sailplane airfoils in
a wind tunnel at Princeton University began on an ambitious scale. The
initial plan was to test 30 airfoils: 15 existing airfoils and 15 new
airfoils to be designed concurrently with the test. As news of the project
caught the attention of radio control model soaring enthusiasts, the
project grew far beyond the original goals and expectations, thanks to
their generosity. When the experimental apparatus was finally dismantled
in January 1989, almost two and a half years later, over 60 models were
tested and over 130 airfoil polars were generated. It is our hope that the
results of this work will be valuable to modelers and researchers for many
years to come.
******************************************************************************
* LOW REYNOLDS NUMBER AIRFOIL VIDEO (VHS)
* Available from: John Donovan
754 Stone Canyon Dr.
Manchester, MO 63021
* Approximately 30 minutes long
* $20 continental USA & Canada
* Summary:
To offset some of the debt incurred during the testing phase of this
project, a video tape was made to document the experiments and
explain some of the aerodynamics of model airplane airfoils.
The wind tunnel, measurement apparatus, and test procedure are explained
showing the tunnel and data taking in operation.
The effects of the drag-producing laminar separation bubbles
are explained. Through specific examples, airfoils well suited for
F3B, multi-task, and cross-country flying are discussed.
*******************************************************************************
* AIRFOILS AT LOW SPEEDS DATA DISK
* Available from: David B. Fraser
1335 Slayton Drive
Maple Glen, PA 19002
* Airfoil performance data and coordinates on computer disk as ASCII files
* IBM 3 1/2 inch and 5 1/4 inch disks, and Macintosh
* $12 continental USA & Canada
*******************************************************************************
* Selected References as of Oct 89:
Flying Models June 88, p. 69
Jan 89, p. 66
April 89, p. 71
July 89, p. 64
Sept 89, p. 64
Oct 89, p. 66, 67
Model Aviation Aug 88, p. 169, 172
Aug 89 p. 168, 169
Sept 89, p. 40
Oct 89, p. 48
Model Builder Nov 88, p. 38, 39, 105
Dec 88, p. 40, 41, 42, 43
Feb 89, p. 88, 89
Aug 89, p. 93
*******************************************************************************
* Please feel free to pass this information along,
since there is no formal advertising.
******************************************************************************
SD7003 8.5%
1.00000 0.0
0.99681 0.00031
0.98745 0.00132
0.97235 0.00310
0.95193 0.00547
0.92639 0.00824
0.89600 0.01139
0.86112 0.01494
0.82224 0.01884
0.77985 0.02304
0.73449 0.02744
0.68673 0.03197
0.63717 0.03649
0.58641 0.04086
0.53499 0.04494
0.48350 0.04859
0.43249 0.05171
0.38250 0.05415
0.33405 0.05581
0.28760 0.05658
0.24358 0.05639
0.20240 0.05518
0.16442 0.05292
0.12993 0.04961
0.09921 0.04526
0.07244 0.03993
0.04978 0.03372
0.03130 0.02677
0.01702 0.01932
0.00697 0.01172
0.00127 0.00438
0.00025 -0.00186
0.00457 -0.00741
0.01408 -0.01285
0.02839 -0.01759
0.04763 -0.02141
0.07182 -0.02438
0.10073 -0.02660
0.13407 -0.02809
0.17150 -0.02888
0.21268 -0.02900
0.25719 -0.02852
0.30456 -0.02752
0.35426 -0.02608
0.40572 -0.02428
0.45837 -0.02217
0.51161 -0.01980
0.56484 -0.01723
0.61748 -0.01450
0.66898 -0.01167
0.71883 -0.00887
0.76644 -0.00628
0.81118 -0.00403
0.85241 -0.00220
0.88957 -0.00082
0.92210 0.00008
0.94952 0.00052
0.97134 0.00057
0.98718 0.00037
0.99679 0.00011
1.00001 -0.00000
Michael Selig
Penn State, Dept. of Aerospace Eng.
233 Hammond Bldg.
University Park, PA 16802
e-mail: ms2@psuecl.bitnet
|
| 1113.35 | New airfoil for F3B/E gliders | KBOMFG::KLINGENBERG | | Tue Feb 06 1990 11:21 | 139 |
| 1113.36 | | CLOSUS::TAVARES | Stay Low, Keep Moving | Tue Feb 06 1990 14:04 | 41 |
| Harmut, take a look at the postscript program that I entered
earlier. Notice the format that the numbers are entered in; the
stations (left hand column of your listing) are in percent and
you need to move the decimal point over two places to get yours
to work.
The right hand column of offsets is a little harder. I usually
look for the largest numbers in the listing and make them the
first significant digit after the decimal; as 0.xxxx. Then I add
zeros to preserve the proportion for the offsets.
Also, when entering the bottom coordinates, you will find that
the first run gives you two positively cambered lines. You have
to go back and change the sign of the bottom coordinates to
negative, but watch out if the foil has an undercamber -- it will
be given as a negative number, so you'll change the sign to
positive to plot those numbers. Its easier done than said, and
if you take the time to fool with it you'll see how it works.
A little trial and error goes a long way. I will enter the foil
in my office, then go into the printer room and run several
copies while I adjust the numbers. This is especially important
when entering numbers in the normally given format where the
first number after the nose is 1/8 inch in -- I have to enter
numbers at 1/32, 1/16, and often at 1/64 to get a nice curve to
the nose.
I have been plotting my latest foils in landscape (sideways on
the 8 1/2x11 paper) rather than in portrait (vanilla flavor).
This means that the position coordinates on the paper, down at
the last part of the program where you insert the name of the
foil, are changed. I haven't mentioned anything further about
this, but I've improved the program a little so its a little
easier to position the foil on the paper and enter coordinates.
Its not good enough yet to post here. For starters though, you
should print out the Clark Y foil that I give in my posting and
see how the coordinates are entered. From there its a piece of
cake to stick in your foil.
Really, stick with it and you'll see some beautiful foils; its
the only way to go!
|
| 1113.37 | DU86-084/18 - Corrected Coordinates | AES12::BOBA | Bob Aldea @PCO | Tue Feb 06 1990 14:04 | 116 |
| RE: 1113.35
That is one strange appearing airfoil... The Y coordinates given need
to be devided by 100 to match the X coordinate values. It still looks
a little strange, but it stays on the paper. :^)
A modified set of coordinates follow.
---------------------------------------------------------------------
%DU 86-084/18
%Max. Thickness: 8.47 % at 36.87 % (of chord)
%Flap/Aileron: 18 % (of chord)
%Artificial turbulator at 67% (topside) and 78% (underside)
/DU86084 [
%topside
1.0000000 0.0000000
0.9988200 0.0001447
0.9953665 0.0005830
0.9899013 0.0011925
0.9725984 0.0024032
0.9606422 0.0031488
0.9465337 0.0040844
0.9303528 0.0052965
0.9122220 0.0068370
0.8922955 0.0087690
0.8706801 0.0109809
0.8472141 0.0134217
0.8217831 0.0167666
0.7956653 0.0220332
0.7703317 0.0279601
0.7453438 0.0326522
0.7195940 0.0362654
0.6928009 0.0392896
0.6651482 0.0417247
0.6367622 0.0442331
0.6077684 0.0462555
0.5782917 0.0480102
0.5484557 0.0495081
0.5183809 0.0507531
0.4881872 0.0517501
0.4579983 0.0525045
0.4279392 0.0530151
0.3981293 0.0532781
0.3686865 0.0532933
0.3113605 0.0525702
0.2836955 0.0518325
0.2568385 0.0508479
0.2308928 0.0496201
0.2059593 0.0481538
0.1821350 0.0464516
0.1595123 0.0445172
0.1381801 0.0423513
0.1182156 0.0399464
0.0996773 0.0372991
0.0826129 0.0344198
0.0670670 0.0313251
0.0530788 0.0280381
0.0406880 0.0245893
0.0299290 0.0209987
0.0208118 0.0172896
0.0133511 0.0135292
0.0075531 0.0097171
0.0033386 0.0059511
0.0007521 0.0025174
%underside
0.0000336 -0.0004726
0.0015717 -0.0031004
0.0052525 -0.0057736
0.0108302 -0.0085296
0.0183287 -0.0111716
0.0276332 -0.0137678
0.0387149 -0.0162443
0.0515408 -0.0185711
0.0660709 -0.0207293
0.0822607 -0.0227012
0.1000638 -0.0244734
0.1194246 -0.0260385
0.1402826 -0.0273971
0.1625650 -0.0285504
0.1861926 -0.0294976
0.2110864 -0.0302423
0.2371603 -0.0307960
0.2643152 -0.0311721
0.2924452 -0.0313827
0.3214399 -0.0314417
0.3511781 -0.0313606
0.3815422 -0.0311475
0.4124124 -0.0308161
0.4436585 -0.0303845
0.4751444 -0.0298640
0.5067352 -0.0292648
0.5382890 -0.0285963
0.5696652 -0.0278628
0.6007223 -0.0270638
0.6313174 -0.0262052
0.6613135 -0.0252630
0.6905754 -0.0242250
0.7189732 -0.0230875
0.7463852 -0.0218080
0.7726988 -0.0203913
0.7978017 -0.0187273
0.8215536 -0.0167216
0.8441240 -0.0141497
0.8658740 -0.0110373
0.8868765 -0.0079960
0.9068719 -0.0053887
0.9255052 -0.0033242
0.9424745 -0.0017859
0.9575055 -0.0008113
0.9704050 -0.0002878
0.9810382 -0.0000229
0.9893387 0.0000425
0.9952800 0.0000340
0.9987941 0.0000059
1.0000000 0.0000000
] def
|
| 1113.38 | Thanks for correction - still not working | KBOMFG::KLINGENBERG | | Tue Feb 06 1990 15:39 | 24 |
|
re: last two
Thanks for the help so far. But I don't have the time to go into the
details now. I still get some weird lines from your data, Bob. Maybe
there is a bug in my program or something is wrong with the printer
setup. I get two lines on top of the paper, crossing at a very small
angle, and two line at the bottom that could be something from the
topside coordinates, but the first starts at ~2/3 of chord, runs
forward to the nose and goes on with the trailing edge up to ~2/3 of
chord again. Second line is the same, but starts and ends at ~1/3.
While entering the data, you are right, I made that mistake. The list
was written in percent, but I found in some of the data here that
x-coordinates ran from 0.0 to 1.0. So I divided the x-values, but
forgot to do so with the y-values.
When the profile you get, Bob, looks only a little strange, it is
probably correct. Thanks again for the corrected coordinates.
Regards,
Hartmut
|
| 1113.39 | Maybe its the device type?? | CLOSUS::TAVARES | Stay Low, Keep Moving | Tue Feb 06 1990 16:20 | 18 |
| That is strange, its something I haven't seen so far and I don't
know what would cause it. The only thing similar I've seen is
when you fail to make the lower coordinates negative; as I said
before, it gives you the top half ok, but inverts the lower
coordinates line.
Bob entered his note at the same time as mine, and between the
two it should cover any problem with the program or entering
data: perhaps its something with your printer, did you specify a
postscript file on your command line? If you don't the printer
will assume a device type of LN03, LPS40, or etc.
I use the rule of taking the highest numbers in the coordinate
list and making them the first digit after the decimal point,
then adjusting the coordinates to match because I've found
different systems for specifying the coordinates in various
sources -- though the "two decimal places over" is the general
rule.
|
| 1113.41 | Plot airfoils with Postscript | K::FISHER | Only 35 Days till Phoenix! | Fri Feb 09 1990 15:33 | 9 |
| > Is there software available somwhere to plot airfoils, either
> under VMS or under MSDOS.
Sure is - see note 1113.17 and 1113.27.
Bye --+--
Kay R. Fisher |
---------------O---------------
################################################################################
|
| 1113.40 | SD6080 Coordinates | AES12::BOBA | Bob Aldea @PCO | Fri Feb 09 1990 20:05 | 70 |
| Another for the collectors...
(Previously entered but deleted due to a typo)
% An improved version of S4061 which worked
% very well in the Prodigy 2M model & others.
/SD6080 [
1.00000 0.00000
0.99676 0.00037
0.98716 0.00159
0.97155 0.00383
0.95032 0.00717
0.92398 0.01160
0.89301 0.01704
0.85799 0.02332
0.81945 0.03025
0.77793 0.03758
0.73396 0.04508
0.68807 0.05250
0.64077 0.05960
0.59257 0.06613
0.54399 0.07185
0.49546 0.07646
0.44730 0.07980
0.39986 0.08176
0.35351 0.08234
0.30859 0.08154
0.26547 0.07941
0.22453 0.07607
0.18616 0.07160
0.15071 0.06609
0.11851 0.05965
0.08984 0.05238
0.06490 0.04442
0.04387 0.03595
0.02684 0.02720
0.01391 0.01844
0.00509 0.01004
0.00045 0.00260
0.00082 -0.00296
0.00692 -0.00710
0.01860 -0.01060
0.03565 -0.01322
0.05796 -0.01494
0.08539 -0.01581
0.11771 -0.01592
0.15462 -0.01539
0.19573 -0.01433
0.24059 -0.01285
0.28870 -0.01109
0.33948 -0.00916
0.39233 -0.00717
0.44662 -0.00519
0.50168 -0.00334
0.55682 -0.00166
0.61136 -0.00020
0.66463 0.00099
0.71596 0.00189
0.76470 0.00250
0.81024 0.00282
0.85200 0.00287
0.88944 0.00267
0.92207 0.00228
0.94944 0.00175
0.97121 0.00118
0.98707 0.00063
0.99675 0.00018
1.00001 0.00000
] def
|
| 1113.42 | Eppler 168 & 197 | K::FISHER | Only 29 Days till Phoenix! | Thu Feb 15 1990 13:24 | 149 |
| From the UUCP net.
Bye --+--
Kay R. Fisher |
---------------O---------------
################################################################################
Article 2106
From: ms2@psuecl.bitnet
Newsgroups: rec.models.rc
Subject: Re: airfoil question/request
Date: 13 Feb 90 18:55:04 GMT
Organization: Engineering Computer Lab, Pennsylvania State University
In article <22215.25d764c9@kuhub.cc.ukans.edu> nesmith@kuhub.cc.ukans.edu writes
>Does anyone have the coordinates for the Eppler168 and 197 airfoils?
Eppler 168
1.00000 0.00000
0.99649 0.00021
0.98631 0.00108
0.97018 0.00271
0.94855 0.00476
0.92146 0.00706
0.88914 0.00979
0.85210 0.01306
0.81090 0.01691
0.76616 0.02130
0.71854 0.02615
0.66871 0.03135
0.61736 0.03673
0.56516 0.04211
0.51275 0.04728
0.46075 0.05200
0.40972 0.05606
0.36019 0.05924
0.31262 0.06134
0.26739 0.06221
0.22485 0.06177
0.18536 0.05995
0.14915 0.05672
0.11641 0.05211
0.08730 0.04627
0.06198 0.03944
0.04069 0.03187
0.02363 0.02380
0.01095 0.01550
0.00287 0.00733
0.00000 0.00000
0.00287 -0.00733
0.01095 -0.01550
0.02363 -0.02380
0.04069 -0.03187
0.06198 -0.03944
0.08730 -0.04627
0.11641 -0.05211
0.14915 -0.05672
0.18536 -0.05995
0.22485 -0.06177
0.26739 -0.06221
0.31262 -0.06134
0.36019 -0.05924
0.40972 -0.05606
0.46075 -0.05200
0.51275 -0.04728
0.56516 -0.04211
0.61736 -0.03673
0.66871 -0.03135
0.71854 -0.02615
0.76616 -0.02130
0.81090 -0.01691
0.85210 -0.01306
0.88914 -0.00979
0.92146 -0.00706
0.94855 -0.00476
0.97018 -0.00271
0.98631 -0.00108
0.99649 -0.00021
1.00000 0.00000
Eppler 197
1.00000 0.00000
0.99642 0.00050
0.98604 0.00219
0.96960 0.00530
0.94778 0.00961
0.92096 0.01478
0.88939 0.02069
0.85349 0.02733
0.81384 0.03467
0.77105 0.04254
0.72575 0.05080
0.67860 0.05921
0.63028 0.06753
0.58146 0.07543
0.53282 0.08247
0.48475 0.08808
0.43735 0.09193
0.39085 0.09396
0.34551 0.09415
0.30160 0.09252
0.25933 0.08920
0.21903 0.08444
0.18112 0.07846
0.14599 0.07142
0.11402 0.06348
0.08551 0.05481
0.06075 0.04559
0.03996 0.03603
0.02335 0.02636
0.01104 0.01686
0.00318 0.00792
0.00000 0.00023
0.00279 -0.00637
0.01164 -0.01275
0.02555 -0.01891
0.04438 -0.02452
0.06797 -0.02947
0.09610 -0.03366
0.12852 -0.03702
0.16493 -0.03954
0.20495 -0.04118
0.24818 -0.04196
0.29413 -0.04186
0.34231 -0.04078
0.39236 -0.03857
0.44415 -0.03537
0.49723 -0.03162
0.55091 -0.02762
0.60447 -0.02359
0.65718 -0.01967
0.70834 -0.01598
0.75725 -0.01262
0.80323 -0.00965
0.84564 -0.00711
0.88388 -0.00500
0.91738 -0.00327
0.94572 -0.00182
0.96864 -0.00070
0.98572 -0.00008
0.99637 0.00004
1.00000 0.00000
Michael Selig
Penn State, Dept. of Aerospace Eng.
233 Hammond Bldg.
University Park, PA 16802
e-mail: ms2@psuecl.bitnet
|
| 1113.46 | Anyone got these disks? | POBOX::KAPLOW | Set the WAYBACK machine for 1982 | Fri Apr 06 1990 17:38 | 27 |
| >******************************************************************************
>* AIRFOILS AT LOW SPEEDS DATA DISK
>* Available from: David B. Fraser
> 1335 Slayton Drive
> Maple Glen, PA 19002
>* Airfoil performance data and coordinates on computer disk as ASCII files
>* IBM 3 1/2 inch and 5 1/4 inch disks, and Macintosh
>* $12 continental USA & Canada
>******************************************************************************
Has anyone ordered either this data disk, or the ibm/pc saleplane
design software that David Fraser offers? I'm interested both, but
don't have a pc or clone to use them on. The data, once transfered
to VMS should be usable by the software in earlier replies. I'd be
interesting in porting or reimplementing the sailplane design
tools for VMS as well.
If this isn't available onthe net somewhere, I think I'll order at
least the data disk, and seek the aid of a DOS friend to get it
here.
I do have (somewhere, I just moved and most of my shop is still
packed) the Stalick "Darn Good Airfoil" book. When I find it, I'll
start typing in some more airfoil coordinates. I also have
additional stuff already typed up, burried with my unpacked
computer stuff. If there is interest, when found, I'll post them
here.
|
| 1113.47 | I have them | CURIE::ANKER | Anker Berg-Sonne | Sun Apr 08 1990 15:35 | 7 |
| Re: <<< Note 1113.46 by POBOX::KAPLOW "Set the WAYBACK machine for 1982" >>>
I have them. What do you want? I have the airplane
design disks on order and am sure I'll get them by the end of the
week.
Anker
|
| 1113.48 | Data disk is copyrighted... | ROCK::MINER | Dan Miner, DTN:225-4015, HLO2-3/D11 | Mon Apr 09 1990 17:48 | 27 |
| RE: Note 1113.46 by POBOX::KAPLOW
I have the data disk. When I ordered it, I wrote a note to David
Fraser asking him if it would be OK to post the data on a "bulliten
board" (closest layman's translation of Notes).
He wrote back a letter explaining that it would be a violation of
the copyright to do so. This is confusing since all of the stuff
that Michael Selig is posting on the Internet he claims is "public
domain".
Bottom line: I have the disk and won't post the data here since I
don't want to violate the copyright. I like my job too much to get
fired because I broke one of DEC's rules that you may not post
copyrighted information without the author's permission... (Is this
REALLY a DEC rule or just a moral issue???)
_____
| \
| \ Silent POWER!
_ ___________ _________ | Happy Landings!
| \ | | | | |
|--------|- SANYO + ]-| ASTRO |--| - Dan Miner
|_/ |___________| |_________| |
| / | " The Earth needs more OZONE,
| / not Caster Oil!! "
|_____/
|
| 1113.49 | More on Data disk | ROCK::MINER | Dan Miner, DTN:225-4015, HLO2-3/D11 | Mon Apr 09 1990 17:53 | 25 |
| RE: .48
After I entered the last note, I just realized that the airfoil
coordinates may be "public domain" but all of the lift/drag data
that was gathered from the airfoils may be the part that is
copyrighted.
In my letter to David Fraser, I just asked if I could post ALL of
the disk to the BBS. I did not ask if I could post ONLY the airfoil
coordinates...
Does someonene else want to write him a letter and ask if it's OK to
post ONLY the airfoil coordinates? If I see a ocpy of a letter from
him stating it's OK to do so, I'll post any/all data from the disk.
_____
| \
| \ Silent POWER!
_ ___________ _________ | Happy Landings!
| \ | | | | |
|--------|- SANYO + ]-| ASTRO |--| - Dan Miner
|_/ |___________| |_________| |
| / | " The Earth needs more OZONE,
| / not Caster Oil!! "
|_____/
|
| 1113.50 | I'll volunteer to contact Dave... | POBOX::KAPLOW | Set the WAYBACK machine for 1982 | Mon Apr 09 1990 19:47 | 16 |
| The data disk is copyrighted? Too bad. I was hoping that the stuff
was in the public domain, as the info from Mr. Selig had
indicated. $12 sounded like the cost to cover an order, not a
profit making venture. I'd be glad to contact Mr. Fraser and
clarify this situation. Does he have an internet address?
As to what I'm looking for, I was most interested in saving the
typing of the data on the disk. I have just ordered Soartech #8,
and assumed that this disk was not much different than an ASCII
copy of most of that report.
As to the sailplane design program, I do not have nor desire a dos
system, and was hoping to port the program, or to reimplement the
algorithm to something that would run on VMS.
Bob
|
| 1113.51 | Soartechs available | ABACUS::RYDER | perpetually the bewildered beginner | Tue Apr 10 1990 11:22 | 9 |
| re .-1
Unlike all of the previous Soartechs, Soartech #8 *is* copyrighted.
The earlier Soartechs explicitly encouraged copying.
FWIW, I have Soartechs 1 through 8. Copies of 1 through 7 are
available from myself and Kay with the provision that recipients make
copies available to others --- Kay's idea for a sort of a chain letter
strategy for spreading the word without a burden on any one person.
|
| 1113.52 | Soartech #8 and Data disk | ROCK::MINER | Dan Miner, DTN:225-4015, HLO2-3/D11 | Tue Apr 10 1990 15:30 | 42 |
| RE: Note 1113.50 by POBOX::KAPLOW
Like I said in .49, I think the airfoil profile (shape) data may be
considered public domain but the lift/drag data may be the part that
is copyrighted. If you can get this clarified, I will post all of
the data that we have legal permission to post.
No, I don't know of an internet address for Mr. Fraser. Maybe
Michael Selig could give you his address if one exists.
> As to what I'm looking for, I was most interested in saving the
> typing of the data on the disk. I have just ordered Soartech #8,
> and assumed that this disk was not much different than an ASCII
> copy of most of that report.
I have both the disk and Soartech #8. The book has all of the
lift/drag data in the form of graphs but not listed as tables of
numbers (at least as I recall). The disk contains the tables of
numbers and it is up to you to convert these tables into graphs if
you desire.
The book also contains pictures and text that is not on the disk.
Part of the book is devoted to statements and comparisons like
"Airfoil xxx is good for thermal events while airfoil yyy would be
better suited for F3B events..." Basically the disk contains only
tables of numbers for the airfoil shapes and how they performed in
the wind tunnel.
Bottom line is that it's worthwhile to have both. If you want to
pick only one or the other, get the book since all of the data on
the disk is in the book too.
_____
| \
| \ Silent POWER!
_ ___________ _________ | Happy Landings!
| \ | | | | |
|--------|- SANYO + ]-| ASTRO |--| - Dan Miner
|_/ |___________| |_________| |
| / | " The Earth needs more OZONE,
| / not Caster Oil!! "
|_____/
|
| 1113.53 | Soartech manuals | K::FISHER | Stop and smell the balsa. | Wed Apr 11 1990 16:27 | 14 |
| > <<< Note 1113.51 by ABACUS::RYDER "perpetually the bewildered beginner" >>>
> -< Soartechs available >-
...
> FWIW, I have Soartechs 1 through 8. Copies of 1 through 7 are
> available from myself and Kay with the provision that recipients make
> copies available to others --- Kay's idea for a sort of a chain letter
> strategy for spreading the word without a burden on any one person.
OK - I will enter a separate note on this - real soon!
Bye --+--
Kay R. Fisher |
---------------O---------------
################################################################################
|
| 1113.54 | | POBOX::KAPLOW | Set the WAYBACK machine for 1982 | Fri Apr 13 1990 03:01 | 8 |
| I wrote and got a prompt reply form Michael Selig. Soartech #8,
and the disks are copyrighted, but he doesn't object to NON-PROFIT
copying, including electronic distribution. His goal in
copyrighting the materials is to prevent others from reselling his
work at a profit. (I do exactly the same with my "works", after
once getting burned on a photo credit by Model Builder) Since the
data disk comes from Dave, I still need to write him to get his
OK. I'll follow this up then.
|
| 1113.55 | Salplane Design program | CURIE::ANKER | Anker Berg-Sonne | Fri Apr 13 1990 13:41 | 4 |
| I have been playing with the Sailplane Design program.
It's really fascinating, but has an abominable user interface.
Anker
|
| 1113.61 | additional .FOIL files available | POBOX::KAPLOW | Set the WAYBACK machine for 1982 | Sat Apr 14 1990 22:14 | 30 |
| I transfered all my old airfoil data from 8" floppy, and
reformated it to match the .FOIL files for the postscript printing
program. Included here is everything I've extracted out of earlier
replies in this conference. I'll leave it online as long as I can
afford the disk space and there is some interest. The files are
each rather small.
I hacked up a program to convert "triples" into the polar
coordinate form tht the postscript code wants. If anyone wants
that, send me mail. Additional contributions are welcome.
Directory POBOX::$2$DUA12:[KAPLOW.ROCKETS.AIRFOIL]
AIRFOIL.COM;1 CLARKY.FOIL;2 CLARK_Y.FOIL;4 DU86_084_18.FOIL;1
E058.FOIL;1 E059.FOIL;1 E168.FOIL;1 E174.FOIL;1
E176.FOIL;1 E178.FOIL;1 E180.FOIL;1 E184.FOIL;1
E193.FOIL;1 E193B.FOIL;1 E195.FOIL;1 E197.FOIL;1
E197B.FOIL;2 E201.FOIL;1 E203.FOIL;1 E205A.FOIL;1
E205B.FOIL;1 E205C.FOIL;1 E207.FOIL;1 E211.FOIL;1
E211B.FOIL;1 E212.FOIL;1 E214.FOIL;1 E214B.FOIL;1
E374.FOIL;1 E385.FOIL;1 E387.FOIL;1 E392.FOIL;1
FX61_163.FOIL;1 HQ1508.FOIL;1 HQ1509.FOIL;1 HQ1510.FOIL;1
HQ1512.FOIL;1 HQ2508.FOIL;1 HQ2510.FOIL;1 HQ2512.FOIL;1
NACA0009A.FOIL;1 NACA0009B.FOIL;4 NACA2415.FOIL;1 NACA6310.FOIL;4
PLATE1.FOIL;1 PLATE5.FOIL;1 RG12A.FOIL;1 S3021.FOIL;1
S3021_095_84.FOIL;5 S4061.FOIL;1 S4180_098_84.FOIL;1 SD6060.FOIL;1
SD6080.FOIL;1 SD7003.FOIL;1
Total of 54 files.
|
| 1113.67 | AIRFOIL.COM & *.FOIL's now available in UK | HAMPS::WARWICK_B | Stay young -- keep your wheels in motion | Wed Apr 18 1990 09:26 | 25 |
| > < Note 1113.61 by POBOX::KAPLOW "Set the WAYBACK machine for 1982" >
> -< additional .FOIL files available >-
>
> I transfered all my old airfoil data from 8" floppy, and
> reformated it to match the .FOIL files for the postscript printing
> program. Included here is everything I've extracted out of earlier
> replies in this conference. I'll leave it online as long as I can
> afford the disk space and there is some interest. The files are
> each rather small.
Many thanks for your efforts -- I have copied the whole lot -- great!
I know that Trevor Hornby down in our Solent office will be interested
as he designs his own gliders and I am getting into gliding also
> I hacked up a program to convert "triples" into the polar
> coordinate form tht the postscript code wants. If anyone wants
> that, send me mail. Additional contributions are welcome.
I would be interested in this also
Thankx again
Brian
|
| 1113.69 | polar.for | POBOX::KAPLOW | Set the WAYBACK machine for 1982 | Thu Apr 19 1990 02:46 | 120 |
| re: a couple back
I've worked for DEC for over 10 years. At least whereever I've
been, I've been addressed as Bob (or perhaps an occasional
unprintable). Last I checked, Mr. Kaplow was my father :-) Maybe
that's what I get for using a "vanity" personal name instead of
something useful.
Here is POLAR.FOR, which is a weekend hack, and only tested under
RT-11 so far. If you run it on a VAX and notice any problems, let
me know, as I try to keep my code interchangable. My permission to
use is extended to cover DEC employees. I put this notice in
everything I write since I once got burned over a copyright issue
by a modelling magazine (not really their fault, but...)
program polar
C
C Program (c) Copyright 1990 by:
C
C Robert G. Kaplow NAR 11286
C 1628 Waterford Ln.
C Palatine, IL 60074
C (312) 934-1160
C
C Non-commercial right to use this software is granted to the
C Academy of Model Aeronautics (AMA), and its members and
C sections, provided that this notice is included in all copies
C of this software. Any other use of this software requires
C the permission of the author.
C
C Program History
C 13-Apr-90 Written - RGK
C
C Convert XYY airfoil triplets to polar format
C for use by postscript plotter
C
implicit complex ( a - z )
C
byte desc ( 50 ) ! description
real factor ! scaling factor
integer i ! loop index
integer in, out ! file unit numbers
data in, out / 1, 2 /
byte infile ( 50 ), outfil ( 50 )! expanded file names
integer keybrd, printr, screen ! file unit numbers
data keybrd, printr, screen / 5, 6, 5 /
integer n ! number of airfoil points
real x ( 100 ) ! chord ordinates
real y1 ( 100 ) ! top ordinates
real y2 ( 100 ) ! bottom ordinates
C
C open input & output files
C
1 write ( screen, 2 )
2 format ( ' Input airfoil file [.air]:', $ )
read ( keybrd, 3, end = 999 ) infile
3 format ( 50a1 )
infile ( 50 ) = 0
open ( unit = in, name = infile, type = 'OLD', err = 1 )
C
4 write ( screen, 5 )
5 format ( ' Output airfoil file [.foil]:', $ )
read ( keybrd, 3, end = 999 ) outfil
outfil ( 50 ) = 0
open ( unit = out, name = outfil, type = 'NEW',
1 carriagecontrol = 'LIST', err = 4 )
C
C read the factor
C
n = 1
6 write ( screen, 7 )
7 format ( ' Scaling factor [usually 1. or 100.]:', $ )
read ( keybrd, 30, end = 100 ) factor
if ( factor .le. 0. ) factor = 1.
if ( factor .gt. 10000. ) factor = 100.
C
C get the data from the input file
C
10 read ( 1, 15, end = 999 ) desc
15 format ( 12x, 50a1 )
if ( desc ( 1 ) .eq. 'X' ) desc ( 1 ) = '%'
write ( 2, 3 ) desc
20 read ( 1, 30, end = 100 ) x ( n ), y1 ( n ), y2 ( n )
30 format ( 3 f 12.4 )
C
if ( x ( n ) .eq. 0. .and. y1 ( n ) .eq. 0. .and.
1 y2 ( n ) .eq. 0. .and. n .gt. 1 ) go to 100
C
C scale the data
C
x ( n ) = x ( n ) / factor
y1 ( n ) = y1 ( n ) / factor
y2 ( n ) = y2 ( n ) / factor
n = n + 1
go to 20
C
C write the upper half of the polar file
C
100 n = n - 1
write ( 2, 110 )
110 format ( '%upper surface' )
do 120 i = 1, n
120 write ( 2, 130 ) x ( i ), y1 ( i )
130 format ( f8.6, 4x, f9.6 )
C
C write the lower half of the polar file
C
write ( 2, 140 )
140 format ( '%lower surface' )
do 150 i = n, 1, -1
150 write ( 2, 130 ) x ( i ), y2 ( i )
C
close ( unit = in )
close ( unit = out )
C
go to 1
C
999 stop 'polar'
end
|
| 1113.72 | SD7003 from the UseNet | K::FISHER | Stop and smell the balsa. | Mon May 07 1990 14:17 | 223 |
|
Article 2440
From: ms2@psuecl.bitnet
Newsgroups: rec.models.rc
Subject: Re: Want SD7003 information
Date: 26 Apr 90 16:30:24 GMT
Organization: Engineering Computer Lab, Pennsylvania State University
Larry,
Here is some data on the SD7003 airfoil. Included:
(1) Coordinates
(2) Wind tunnel data
(3) Theoretical results calculated for a sailplane that had a Reynolds
number of 150,000 at a cl = 1.0. Note that the Reynolds number used in the
calculation increases as the cl decreases, ie. the speed change of the
sailplane in flight is accounted for by changing the Re.
I have heard that this airfoil is doing pretty well in slope racing and some
are considering it for F3B. Of the airfoil tested, the SD7003 airfoil had the
lowest drag at the lower Reynolds numbers so it should be very good for smaller
planes as well.
By flattening the lower surface from about 40% chord to the trailing edge
would not make much difference in the performance. It will mainly lower
the lift range while having little impact on the drag.
Michael Selig
Penn State, Dept. of Aerospace Eng.
233 Hammond Bldg.
University Park, PA 16802
e-mail: ms2@psuecl.bitnet
Coordinates:
SD7003
1.00000 0.0
0.99681 0.00031
0.98745 0.00132
0.97235 0.00310
0.95193 0.00547
0.92639 0.00824
0.89600 0.01139
0.86112 0.01494
0.82224 0.01884
0.77985 0.02304
0.73449 0.02744
0.68673 0.03197
0.63717 0.03649
0.58641 0.04086
0.53499 0.04494
0.48350 0.04859
0.43249 0.05171
0.38250 0.05415
0.33405 0.05581
0.28760 0.05658
0.24358 0.05639
0.20240 0.05518
0.16442 0.05292
0.12993 0.04961
0.09921 0.04526
0.07244 0.03993
0.04978 0.03372
0.03130 0.02677
0.01702 0.01932
0.00697 0.01172
0.00127 0.00438
0.00025 -0.00186
0.00457 -0.00741
0.01408 -0.01285
0.02839 -0.01759
0.04763 -0.02141
0.07182 -0.02438
0.10073 -0.02660
0.13407 -0.02809
0.17150 -0.02888
0.21268 -0.02900
0.25719 -0.02852
0.30456 -0.02752
0.35426 -0.02608
0.40572 -0.02428
0.45837 -0.02217
0.51161 -0.01980
0.56484 -0.01723
0.61748 -0.01450
0.66898 -0.01167
0.71883 -0.00887
0.76644 -0.00628
0.81118 -0.00403
0.85241 -0.00220
0.88957 -0.00082
0.92210 0.00008
0.94952 0.00052
0.97134 0.00057
0.98718 0.00037
0.99679 0.00011
1.00001 -0.00000
Experimental data:
Airfoil - SD7003
Model Builder - MARK ALLEN of Flite Lite Composites, Windsor, CA
5
60300. !Reynolds number
9
-.172 0.0122 -2.95 !cl:cd:alpha
-.039 0.0114 -1.41
0.142 0.0121 0.12
0.370 0.0158 1.67
0.501 0.0193 3.20
0.651 0.0223 4.73
0.779 0.0267 6.26
0.871 0.0399 7.78
0.978 0.0736 9.30
102000.
10
-.138 0.0116 -2.93
-.014 0.0091 -1.41
0.176 0.0125 0.13
0.362 0.0123 1.67
0.494 0.0142 3.20
0.632 0.0158 4.73
0.784 0.0183 6.26
0.904 0.0254 7.78
0.995 0.0356 9.31
0.936 0.1200 10.81
151800.
10
-.119 0.0101 -2.93
0.008 0.0091 -1.40
0.209 0.0095 0.13
0.362 0.0095 1.67
0.511 0.0112 3.19
0.658 0.0143 4.73
0.797 0.0165 6.26
0.917 0.0227 7.79
1.015 0.0325 9.31
0.995 0.0949 10.82
200800.
11
-.115 0.0097 -2.92
0.026 0.0081 -1.40
0.199 0.0079 0.14
0.350 0.0091 1.66
0.507 0.0110 3.20
0.657 0.0128 4.74
0.799 0.0153 6.28
0.926 0.0222 7.80
1.024 0.0308 9.31
0.982 0.1169 10.83
0.905 0.1858 11.82
300300.
15
-.112 0.0093 -2.94
0.000 0.0079 -1.91
0.103 0.0074 -0.90
0.196 0.0072 0.14
0.301 0.0078 1.15
0.409 0.0084 2.18
0.516 0.0095 3.20
0.620 0.0109 4.23
0.719 0.0123 5.25
0.814 0.0138 6.26
0.903 0.0168 7.28
0.983 0.0205 8.31
1.053 0.0253 9.32
1.101 0.0337 10.34
1.098 0.0505 11.32
Data file name PDSD7003
Theoretical results for moments:
XFOIL Version 5.4
Calculated polar for: SD7003
2 Reynolds number ~ 1/sqrt(CL)
xtrf = 1.000 (suction) 1.000 (pressure)
Mach = 0.000 Re = 0.150 e 6 Ncrit = 9.000
c.............................Cm.a.c......VV
alpha CL CD Re(CL) CM S xtr P xtr
------- -------- --------- --------- -------- ------- -------
-1.500 0.0241 0.00650 0.96546 -0.0390 0.7237 0.3068
-1.250 0.0533 0.00657 0.64948 -0.0396 0.7622 0.4487
-1.000 0.0804 0.00643 0.52891 -0.0397 0.7701 0.5940
-0.750 0.1063 0.00643 0.46008 -0.0392 0.7661 0.6927
-0.500 0.1306 0.00646 0.41500 -0.0381 0.7557 0.7731
-0.250 0.1538 0.00654 0.38254 -0.0366 0.7425 0.8325
0.000 0.1748 0.00667 0.35882 -0.0344 0.7223 0.8817
0.250 0.1954 0.00681 0.33932 -0.0321 0.7055 0.9219
0.500 0.2254 0.00698 0.31594 -0.0317 0.6894 0.9758
0.750 0.2719 0.00733 0.28765 -0.0355 0.6685 1.0000
1.000 0.2986 0.00761 0.27449 -0.0353 0.6478 1.0000
1.250 0.3254 0.00788 0.26297 -0.0350 0.6266 1.0000
1.500 0.3517 0.00819 0.25292 -0.0346 0.6003 1.0000
1.750 0.3784 0.00848 0.24384 -0.0343 0.5779 1.0000
2.000 0.4051 0.00878 0.23568 -0.0340 0.5551 1.0000
2.250 0.4314 0.00910 0.22838 -0.0336 0.5282 1.0000
2.500 0.4580 0.00941 0.22165 -0.0332 0.5054 1.0000
2.750 0.4845 0.00973 0.21549 -0.0329 0.4825 1.0000
3.000 0.5106 0.01008 0.20992 -0.0325 0.4550 1.0000
3.250 0.5369 0.01043 0.20471 -0.0321 0.4315 1.0000
3.500 0.5633 0.01078 0.19986 -0.0318 0.4090 1.0000
3.750 0.5895 0.01114 0.19536 -0.0314 0.3866 1.0000
4.000 0.6154 0.01153 0.19121 -0.0310 0.3607 1.0000
4.250 0.6414 0.01193 0.18729 -0.0306 0.3387 1.0000
4.500 0.6673 0.01235 0.18362 -0.0302 0.3174 1.0000
4.750 0.6931 0.01280 0.18017 -0.0298 0.2966 1.0000
5.000 0.7185 0.01327 0.17696 -0.0294 0.2729 1.0000
5.250 0.7440 0.01376 0.17390 -0.0290 0.2536 1.0000
5.500 0.7694 0.01428 0.17101 -0.0285 0.2353 1.0000
5.750 0.7944 0.01480 0.16830 -0.0281 0.2148 1.0000
6.000 0.8194 0.01538 0.16571 -0.0276 0.1981 1.0000
6.250 0.8440 0.01602 0.16328 -0.0271 0.1819 1.0000
6.500 0.8683 0.01664 0.16097 -0.0266 0.1646 1.0000
6.750 0.8923 0.01739 0.15880 -0.0260 0.1496 1.0000
7.000 0.9161 0.01814 0.15672 -0.0254 0.1358 1.0000
7.250 0.9398 0.01880 0.15473 -0.0249 0.1220 1.0000
7.500 0.9629 0.01957 0.15286 -0.0243 0.1080 1.0000
8.000 1.0079 0.02128 0.14941 -0.0230 0.0836 1.0000
8.250 1.0291 0.02242 0.14786 -0.0221 0.0730 1.0000
|
| 1113.73 | NACA 4410 ? | SOLKIM::BOBA | Bob Aldea @PCO | Fri Aug 10 1990 17:46 | 2 |
| I'd appreciate a copy of the coordinates for a NACA4410, in whatever
format you have handy.
|
| 1113.74 | I Don't have a 4410, will two 4405's do? | CLOSUS::TAVARES | John--Stay Low, Keep Moving! | Fri Aug 10 1990 21:25 | 24 |
| I have NACA 4409 coordinates:
station upper lower
0 0.8 0.8
1.25 1.81 -1.05
2.5 2.61 -1.37
5 3.74 -1.65
7.5 4.64 -1.74
10 5.37 -1.73
15 6.52 -1.55
20 7.33 -1.3
25 7.9 -1.02
30 8.25 -0.76
40 8.35 -0.35
50 7.87 -0.07
60 7.0 -0.14
70 5.76 -0.26
80 4.21 -0.26
90 2.33 -0.14
95 1.26 -0.03
100 0.09 -0.09
You'll have to do some fiddling to get a good curve out of these
rough coordinates...when you get it right, shoot us a copy.
|
| 1113.75 | Thanks | SOLKIM::BOBA | Bob Aldea @PCO | Mon Aug 13 1990 12:56 | 5 |
| I'm told that within a NACA series such as 44XX, the proportions are
the same, and the others in the series can be derived by multiplying
the coordinates by a factor that results in the desired thickness.
Assuming that is correct, I'm all set.
|
| 1113.76 | NACA 4410 | SOLKIM::BOBA | Bob Aldea @PCO | Mon Aug 13 1990 16:52 | 51 |
| Here's the NACA4410 estrapolated from the NACA4409 previously posted.
The leading edge, up to 1.25% of the chord, is pure guesstimation but
it looks nice. Who can reliably sand the first 1/8" of the leading
edge that accurately anyhow? The format is suitable for direct
insertion in the Postscript program.
/NACA4410 [
1.0000 .0010
.9500 .0140
.9000 .0259
.8000 .0467
.7000 .0639
.6000 .0777
.5000 .0874
.4000 .0927
.3000 .0916
.2500 .0877
.2000 .0814
.1500 .0724
.1000 .0596
.0750 .0515
.0500 .0415
.0250 .0290
.0125 .0201
.0062 .0139
.0031 .0102
.0015 .0078
.0000 .0000
.0005 -.0017
.0031 -.0056
.0062 -.0085
.0125 -.0117
.0250 -.0152
.0500 -.0183
.0750 -.0193
.1000 -.0192
.1500 -.0172
.2000 -.0144
.2500 -.0113
.3000 -.0084
.4000 -.0039
.5000 -.0008
.6000 -.0016
.7000 -.0029
.8000 -.0029
.9000 -.0016
.9500 -.0003
1.0000 -.0010
] def
|
| 1113.77 | Did you say changing proportions??? | CLOSUS::TAVARES | John--Stay Low, Keep Moving! | Wed Aug 15 1990 01:30 | 7 |
| Bob, I'm home this week, but look forward to firing that one up
in the program.
You casually mentioned changing the proportions with a
multiplying factor. You cannot know how many hours I've
headscratched trying to figure out how to do this...illuminate me
(us) please!
|
| 1113.78 | Altering and combining airfoils | SOLKIM::BOBA | Bob Aldea @PCO | Wed Aug 15 1990 13:39 | 45 |
| I use DECalc-Plus, though any spreadsheet should work. My
understanding of postscript is limited to what I could deduce from
playing with the routines provided in this file. I still haven't
figured out how to get a second page...
I edit the source file to contain only the coordinates and the header
and trailer codes "/FOILNAME [", "] def". Using the "Storage Table"
function to load tabular ascii data, I load the coordinates into the
spreadsheet. If they are already in the format used by the
postscript routine, I'm ready to go. When they are in the XYY format
you provided for the NACA4409, I rearrange them manually. I wind up
with the X coordinates in the leftmost column, and the original Y
coordinates a few columns to the right. Once that has been done, I
use an appropriate value to calculate the new Y coordinates, which are
placed in the column next to the X coordinates, and then print just
those two columns to a file which can be inserted in the program. Once
a grid has been built, its simple to substitute new values (airfoils)
and quickly produce a new set of templates. A word of caution,
postscript will not tolerate a space between the minus sign and the
decimal point.
To convert the NACA4409 to a NACA4410, I multiplied each of the Y
coordinates by 1.11. Within the NACA series, I'm told that's a
legitimate approach.
The same approach can be used to calculate the coordinates for each rib
in a tapered wing with differing root and tip airfoils. For this you
need a set of Y coordinates for each airfoil that correspond to a
matching set of X coordinates. Each rib station's Y coordinates will
be an intermediate value between the root and tip values, in proportion
to its position in the wing. The taper has to be separately calculated
and the size of each rib entered in the postscript routine. I did this
exercise to help a friend who is designing an ME110 which will have a
11 5/8" NACA2415 at the root, which tapers to a NACA 2413, which tapers
to a 4 5/8" NACA4410 at the tip. (He's trying to avoid severe tip
stalling by increasing the camber at the tip)
In a similar way, you could take an existing airfoil, calculate the
camber, and after altering the camber, reverse the process to generate
a new version of the original airfoil. I don't know enough to know how
valuable that approach is, but I know some people do use it.
I hope this is clear enough to answer your question. I'd be happy to
share a DECalc-Plus grid as an example, but I don't know how or if they
can be moved around.
|
| 1113.79 | Multiply by 1.11 eh? | CLOSUS::TAVARES | John--Stay Low, Keep Moving! | Thu Aug 16 1990 03:11 | 22 |
| Ok...ok...1.11 eh? Well, I've looked for a constant, never found
one that works, but I'll try that one. I have an article that
explains how to generate the NACA foils -- BTW, I'm interested in
the 24xx series -- anyway, its a heck of a lot more complicated
than multiplying by 1.11. I'll believe it when I see the 4410
coordinates to compare, or when I can generate a 2415 from a
2412.
I just don't see intuitively that simply multiplying a set of
coordinates, on the curve for the front of the foil for example,
by a constant (read linear function), can yield a same family
curve given the same chord. You can see that the 4410 will be
"higher" for the same chord, yet return to zero at the same
point. Using a linear function only distorts the curve.
Then when we get to OTHER foils, some with more complex
shapes, well, you see the problem.
But then again, I flunked algebra 5 times and still need a
calculator to add 2 numbers, never mind x and y. Anybody
understand curves (mathematical ones, nobody understands the
other kind!) out there?
|
| 1113.80 | NACA airfoils? | SHTGUN::SCHRADER | | Thu Aug 16 1990 12:34 | 9 |
| RE .-1
You have some stuff on how NACA airfoils are generated? If it's algorithmic
then I can implement it in postscript. If I can find some spare moments I'll
post some instructions on how to scale airfoils. The program is already doing
it to set the chord so changing the profile just requires uneven scaling of
the two axes. Stay tuned...
Glenn Schrader
|
| 1113.81 | Anybody else want a copy? | CLOSUS::TAVARES | John--Stay Low, Keep Moving! | Fri Aug 17 1990 03:35 | 6 |
| Glenn, its a complex graph that I'm not sure I know how to read.
Maybe you'll have better luck -- send me mail offline with your
mailstop and I'll send you a copy when I get back next week.
P.S. Thanks again for the airfoil reversing code, I haven't been
able to try it because of deadlines.
|
| 1113.82 | Thickness scaling and multi-page mods to the postscript program. | SHTGUN::SCHRADER | | Mon Aug 20 1990 19:56 | 81 |
| Ok folks, you asked for it you got it!! What follows is a mod to the
Postscript(TM) program that will do two things. First, it allows the
thickness of an airfoil (any airfoil) to be scaled by a factor. Second, it
prints more than one page of stuff.
To cut this into an existing program, delete everything after the airfoil
coordinate array definitions. Ok, now paste in the postscript code which is
at the end of this note and modify the calls to DrawCoords to use your
favorite airfoil, chord, etc. If you want, save your old calls to
DrawCoords and edit them into the code that's you're inserting.
If you don't want to change the airfoil thickness then just call DrawCoords
using the exact save syntax as always. If you want to scale the airfoil
then put in a scaling factor and call the "thickness" function after the
airfoil array parameter. Refer to the following code for examples. If you
don't have an S4061 in your file then change it to whatever you've got
handy if you want to try it out. If you're starting with a 10% thick
airfoil and you want a 12% then use a scaling factor of 1.2
(i.e. 12%/10% = 1.2), if you wanted, say, an 8% then use a scaling factor
of 0.8 (8%/10% = 0.8).
The code fragment that I've included prints two pages. Each page is
generated by a...
save
<stuff>
showpage
restore
...sequence. If you want more than two pages then just replicate the
save-restore blocks for how ever many you need. Delete the second
save-restore block if you only want one page.
I've tested this with a couple of different airfoils and it seems to work
fine.
Glenn Schrader
===================== start of section to insert ======================
/thickness {
/factor ex def
[ex /sss 0 def {sss 0 eq {/sss 1 def}{/sss 0 def factor mul}ifelse}forall]
} def
% Parameters to DrawCoords are ...
% - array of data to use
% - offset from left edge of paper in inches
% - offset from bottom of paper in inches
% - chord in inches
% - label for the airfoil
save
72 72 sc % set scale to inches instead of points
0 setlinecap
0 setlinejoin
0.001 setlinewidth
S4061 1.5 10 3.625 (S4061 3.625) DrawCoords
S4061 1.25 thickness 3.0 10 3.625 (S4061 3.625x1.25) DrawCoords
S4061 1.5 thickness 4.5 10 3.625 (S4061 3.625x1.5) DrawCoords
showpage
restore
save
72 72 sc % set scale to inches instead of points
0 setlinecap
0 setlinejoin
0.001 setlinewidth
S4061 1.1 thickness 1.5 10 7.5 (S4061 7.5x1.1) DrawCoords
showpage
restore
end
%%Trailer
===================== end of section to insert =====================
|
| 1113.83 | A really new airfoil postscript file | SHTGUN::SCHRADER | | Fri Aug 31 1990 17:59 | 70 |
| I've just finished debugging a new rev of the airfoil postscript code. This is
very different from the one in the previous note. It's got a number of really
nifty new features. Rather than put a 500 line note here, if you want a copy
then you can get the file from:
SHTGUN""::DUA1:[PUBLIC.RC]AIRFOIL_V3.PS
This file prints out two pages of sample airfoils.
The biggest change in this version is that I'm using Bezier curves to draw
the lines between coordinate ports rather than straight line segments. This
results in a much smoother drawing especially around the leading edge. One of
the airfoil arrays in the sample file is a very simple airfoil which I
kluged up (named TEST) which has only nine data points. It comes out as a
pretty nice airfoil (nice given that it has so few data points).
If you look at the code where the second page starts you'll see a function
called "mirrorpage". This functions changes the coordinate system so that
everything is printed in a mirror image of it's normal form. This is handy
if you want to do a heat transfer of the page onto balsa or ply (a monokote
iron or regular clothes iron work). When the image is ironed on, the airfoil
labels will not be printed backwards. The second page in the sample file
is a mirror image of the first page.
Then there is the "thickness" and "reverse" functions. The thickness function
scales the thickness of the airfoil coordinates. The reverse function makes
the airfoil print out facing right rather than left. The normal unreversed
airfoils are good for the left hand end of a core. The reversed airfoil is
good for the right hand end of a core. Check the sample file to see how to
use these functions.
As if that weren't enough, there are some variables which can be set to do
some cute things. The following vairable assignments will be at the start
of each page in the sample file:
/skin 1 32 div def
/leading 3 8 div def
/trailing 0.75 def
The value of the skin variable should be set to the thickness of whatever
material the core is to be skinned with (1/32 of an inch in the sample).
What happens is that a second airfoil line is drawn inside of the real airfoil.
The second line is drawn such that it is below the surface of the real airfoil
by the distance set in the skin variable. What you can do is to cut the core
at the inner line which allows for the skin thickness then when the skins
are added the airfoil will have the proper shape.
The value of the leading vairable should be set to the thickness of the stock
which will be used for the leading edge(3/8 of an inch in the sample).
What this does is draw a vertical line set back from the tip of the leading
edge by the value of the leading vairable. The inner skin lines also get
clipped at this point.
The value of the trailing vairable should be set to the width of the stock
which will be used for the trailing edge. This produced a trailing edge
effect which is identical to what the leading variable does to the leading edge.
The format of the coordinate arrays have not changed so if you want to use
some airfoil that you've put in or gotten from a previous version then just
paste it in and use it. One drawback to this version is the amount of time it
takes to print. This is probably because the Bezier curves cause the printer
to spend a bunch of time calculating the curves that go between coordinate
points. On an LN03R, it takes about six (yes, 6) minutes to print both pages
in the sample. There are 10 airfoils that are plotted so that comes out to
about 0.6 minute per airfoil. If you're going to make rib templates for a
large tapered wing then you should expect to wait for a while...
Enjoy,
Glenn Schrader
|
| 1113.84 | how to print these airfoils | GENRAL::KNOERLE | | Fri Aug 31 1990 21:07 | 33 |
|
I printed these airfoils, they come out very nice. I'm playing with
different multipliers now to try to strech (sp?) airfoils to
each length I want to have. It shure works great ! For those of
you rising the same question : 'How to print ?' here's the answer
from Glenn : (GREAT JOB, GLENN !)
From: SHTGUN::SCHRADER 31-AUG-1990 14:06:30.07
To: 8672::KNOERLE
CC: SCHRADER
Subj: RE: HOW TO PRINT airfoil_v3.ps ?
Hi.
You'll need to find a printer queue that is connected to a postscript
print (LN03R, LPS10, or LPS20). Print it using this command:
PRINT/QUE=YOUR_QUEUE/PARAM=DATA=POST AIRFOIL_V3.PS
depending on exactly how your printer is set up you may need the following
instead:
PRINT/QUE=YOUR_QUEUE/PARAM=DATA=POST/FORM=1109 AIRFOIL_V3.PS
One of these should work but if they don't then you should ask your system
manager. Every now and then I run across one that's set up a little wierd.
Good luck, let me know how you make out,
Glenn Schrader
|
| 1113.85 | Some Notes on Airfoil_V3 | CLOSUS::TAVARES | John--Stay Low, Keep Moving! | Wed Sep 05 1990 16:36 | 72 |
| Kudos Glenn! That program is really slick.
Some notes on usage. If you use the program to make balsa rib
templates, set the skin thickness to 1/128 or so. The leading
edge and trailing edge parameters should be set as required for
your model. Its a lot easier to specify phoney values for these
parameters than to simply comment them out, since they're used in
several places.
Remember that you have 2 pages there, so cut your foil line out
of the first page and duplicate it on the second. You also need
to re-specify the le, te, and skin thickness for the second page,
I don't know why...
As noted in the program, the specification line for the program
is the same as the one in the previous version. Because the
program prints default landscape, I like to think of the specify
line as:
ARRAY thickness reverse bott_offset edge_offset chord (label)
where:
Array is the name you entered after the "/" when you entered the
array.
thickness and reverse -- I haven't used so no comment
bott_offset is the offset in inches from the bottom of the
landscape page (that is, the vertical position of the foil)
edge_offset is the offset in inches from the right edge of the
landscape page (that is, the horizontal position of the foil).
label is anything you want to be printed inside the airfoil. The
type size is automatically adjusted for size, but don't try to
write the Gettysburg Address in there!
Both offsets are with reference to the position of the NOSE of
the foil, specifically the point where the mean chord line
crosses the nose curve.
I add the above because this is confusing, since postscript offsets
are usually thought of with reference to the lower left corner of
the portrait page, and that appears to be the way Glenn has
entered the instructions in the program.
For example, the following line:
clarky 4.0 13.5 12.0 (CLARK_Y) DrawCoords
positions the start of the foil array clarky 4.0 inches up from
the bottom and 13.5 inches from the right edge of the paper (I
used 11x17 paper), and draws a 12.0 inch chord foil. It puts the
label CLARK_Y in the center of the foil. Be sure you enter the
DrawCoords in the exact manner given, as postscript is case
sensitive -- that is, it doesn't understand drawcoords,
Drawcoords, drawCoords, or DRAWCOORDS.
I used the command line qualifiers for the print:
/parameters=(Input_tray=middle,sides=1) in my print command line.
Our LPS20 has 11x17 paper in the middle tray, and default prints
2-sided. I mention this here because you may have the same
problem.
I printed out a 12-inch chord Clark_Y foil with this program, and
it is absolutely superb. I will be using the pattern to make
balsa ribs.
Now, what would you suppose John is up to? ;-)
|
| 1113.86 | coordinates of RG15 | GENRAL::KNOERLE | | Wed Sep 05 1990 17:58 | 77 |
|
I've got the cordinades (sp?) of RG15 from a nice guy here in CXO from
a personal computer program and converted it to the format used
in this airfoil_v3 program. It came out perfect (I think). Are
there other airfoils around ?
BTW, John, thickness works perfect.
Holm- und Rippenbruch, Bernd
/RG15 [
1.00000 0.0
0.99671 0.00054
0.98726 0.00229
0.97237 0.00514
0.95248 0.00865
0.92764 0.01254
0.8981 0.01685
0.86427 0.02152
0.8266 0.02644
0.78557 0.03149
0.74165 0.03654
0.69537 0.04146
0.64723 0.04612
0.59778 0.05039
0.54753 0.05414
0.49702 0.05727
0.44676 0.05966
0.39727 0.06123
0.34902 0.0619
0.30248 0.06162
0.25809 0.06036
0.21624 0.0581
0.1773 0.05486
0.14161 0.05068
0.10945 0.04564
0.08108 0.03985
0.05673 0.03343
0.03658 0.02654
0.02076 0.01935
0.00932 0.01214
0.00235 0.00526
0.00000 0.00000
0.00002 -0.00048
0.00336 -0.00534
0.01247 -0.01006
0.0267 -0.01436
0.04596 -0.01811
0.0701 -0.02123
0.09896 -0.02372
0.13224 -0.02559
0.16963 -0.02688
0.21073 -0.02762
0.25509 -0.02785
0.30221 -0.02762
0.35156 -0.02696
0.40257 -0.0259
0.45463 -0.02446
0.50713 -0.02262
0.55944 -0.02025
0.61128 -0.01717
0.66244 -0.01366
0.71237 -0.01015
0.76037 -0.00691
0.80575 -0.00413
0.84779 -0.00192
0.88583 -0.00034
0.91925 0.00062
0.94748 0.00101
0.97003 0.00097
0.98652 0.00064
0.9966 0.00021
1.0000 0.00000
] def
|
| 1113.87 | Reference to Coordinate Note | CLOSUS::TAVARES | John--Stay Low, Keep Moving! | Wed Sep 05 1990 19:54 | 10 |
| Bernd: refer to note 1113.61 where Bob Kaplow posts the location
of a whole treasure trove of airfoil coordinates. I also have
some other foils, mostly freeflight.
Since you're in the neighborhood, contact me offline and I'll see
what I can send you in hardcopy (gotta promise to share the
coordinates once you enter them!). I haven't used these other
listings because with the previous versions of this program, I've
had to fiddle to get the nose right; this program does the dirty
stuff for you and does it "close enough for Government Work".
|
| 1113.88 | And thick enough to store your lunch in | ELMAGO::TTOMBAUGH | High Plains Drifter | Wed Sep 05 1990 20:13 | 7 |
| Likewise I'm impressed with Glenn's program. That x1.5 S4061 really
cracked me up. At first I thought it was some kind of blimp. Buuuut
now I think that maybe I'll try it on about a 7-8 in. chord HLG
wing. No doubt will be slow, but should give a whole new meaning
to the word *floater*.
Terry
|
| 1113.89 | Best of both worlds | KAY::FISHER | Stop and smell the balsa. | Thu Sep 06 1990 12:30 | 16 |
| Glenn Schrader or Mark Antry
Could you guys adapt the new Glenn Schrader post script code to work under
a com file like Mark Antry did in note 1113.17.
It is really neat that you can specify sheeting thickness and leading
and trailing edge stuff but this needs to be input from a com file
and the program should be able to pick form a directory full of various
airfoils.
After that - I can think of half a dozen other enhancements :-)
Bye --+--
Kay R. Fisher |
---------------O---------------
################################################################################
|
| 1113.90 | I'll work on it today and get it in by Friday I hope..... | NEURON::ANTRY | | Thu Sep 06 1990 14:25 | 0 |
| 1113.91 | OK here it is....Glenn's new postscript code with my New DCL code...PLOT AWAY!!!! | NEURON::ANTRY | | Fri Sep 07 1990 15:05 | 316 |
| OK here it is. I modified Glenn's postscript code somewhat. This comm proc
will produce a Postscript file that contains the airfoil requested, it does
4 plots per page. Normal, reversed, normal mirror, reversed mirror.
Now were was that Killer RG-15 airfoil that Bernd put in. I am flying that on
my F3b ICON, you want to see a plane that will zoom launch, wow, that airfoil
is fast and slippery.
Any questions on the Command procudure don't hesitate to either send mail or
give me a call. DTN 523-2163
Mark Antry
------------------------------CUT HERE------------------------------------
$!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
$! AIRFOIL - A command procudure that will plot Airfoils onto
$! Postscript printers.
$!
$! Sept 7, 1990
$!
$! DCL commands by Mark Antry
$! Postscript code by Glenn Schrader
$!
$! Inputs - Airfoil data file
$! Note: The Airfoil data file should contain only the station data
$! in two column format with no header or trailing data...
$! (JUST THE NUMBERS) The com proc will add the header and
$! trailer records when it reads the data into the postscript
$! file. The file name must end in ".FOIL"
$! Airfoil Cord Length
$! Thickness Scaling factor [optional]
$! Leading Edge stock width [optional]
$! Trailing Edge stock width [optional]
$! Skin thickness [optional]
$! Outputs - Postscript output file
$!
$ close/nolog infile
$ open/read infile sys$command:
$getfoil:
$ read/prompt= -
"Enter the Airfoil you wish to plot (ex. S3021) <RET> for list: " infile foiln
$ if foiln .nes. "" then goto gotfoil
$ dir/column=4 *.foil
$ goto getfoil
$gotfoil:
$ dir/out=nl: 'f$parse(foiln,".foil")'
$ if $status then goto foilok
$ write sys$output "ERROR - Specified Airfoil not found"
$ goto getfoil
$foilOK:
$ open/read infoil 'f$parse(foiln,".foil")'
$ read/prompt= -
"Enter the Airfoil Cord length (ex. 10.0, 9.5): " infile fsize
$ if fsize .eqs. "" then fsize = "10.0"
$ read/prompt= -
"Enter the Scaling Thickness factor (EX: 1.0, .95, 1.10) [1.0]: " infile Scale
$ if Scale .eqs. "" then Scale = "1.0"
$ !
$ x = f$locate(".",fsize)
$ if x .eq. f$length(fsize)
$ then psout = foiln + fsize + ".ps"
$ else
$ psout = foiln + f$extract(0,x,fsize) + "_"
$ psout = psout + f$extract(x+1,(x+1-f$length(fsize)),fsize) + ".ps"
$ endif
$ type sys$input
Next Enter the values for the width of any leading or trailing edge stock.
This will cause a line to be drawn on the airfoil plot at those locations.
Enter these values in decimal equivalents:
1/4" = .25 3/8" = .375 1/2" = .5 3/4" = .75 and so on...
$ read/prompt= -
"Enter the value of the Leading edge stock if any [0.0]:" infile leade
$ if leade .eqs. "" then leade = "0.0"
$ read/prompt= -
"Enter the value of the trailing edge stock if any [0.0]:" infile traile
$ if traile .eqs. "" then traile = "0.0"
$ read/prompt= -
"Enter the value of the skin thickness if any (1/32 = .03125 1/16 = .0625)[0.0]:" -
infile skint
$ if skint .eqs. "" then skint = "0.0"
$ close/nolog infile
$!!!!! Place first half of POSTSCRIPT CODE HERE
$ copy/nolog sys$input: 'psout'
%!PS-Adobe-2.0 EPSF-1.2
%%Title: AIRFOILS.PS
%%Creator: G SCHRADER
%%CreationDate: 08/20/90
%%Pages: 2
%%BoundingBox:
% VER 2.0
% added thickness function
% added reverse function
% VER 3.0
% modified to use Bezier curves
% added leading edge, trailing edge, skin thickness
% added mirrorpage function
%%EndComments
%%BeginProlog
/AirfoilDict 150 dict def
AirfoilDict begin
/cl /closepath load def
/ex /exch load def
/gs /gsave load def
/gr /grestore load def
/li /lineto load def
/mo /moveto load def
/rm /rmoveto load def
/np /newpath load def
/rl /rlineto load def
/ro /rotate load def
/sh /show load def
/sc /scale load def
/st /stroke load def
/tr /translate load def
/cp /clip load def
/vec 300 array def
/dst 300 array def
/dta 300 array def
/thickness {
/factor ex def
[ex /sss 0 def {sss 0 eq {/sss 1 def}{/sss 0 def factor mul}ifelse}forall]
} def
/reverse {
[ex /sss 1 def {sss 0 eq {/sss 1 def}{/sss 0 def 1 ex sub}ifelse}forall]
} def
/mirrorpage { clippath pathbbox pop ex pop add 0 tr -1 1 scale } def
/makeopenvectors
{
2 2 dsize 3 sub {
/i ex def
% middle vectors
/dx dta i 2 add get dta i 2 sub get sub def
/dy dta i 3 add get dta i 1 sub get sub def
/dabs dx dup mul dy dup mul add sqrt def
vec i dx dabs div put vec i 1 add dy dabs div put
% middle back distance
/dstb dta i get dta i 2 sub get sub dup mul
dta i 1 add get dta i 1 sub get sub dup mul add sqrt def
% middle front distance
/dstf dta i 2 add get dta i get sub dup mul
dta i 3 add get dta i 1 add get sub dup mul add sqrt def
dst i dstb dabs dstb dstf add div dup 2 div 2 add div mul put
dst i 1 add dstf dabs dstb dstf add div dup 2 div 2 add div mul put
} for
%start vector
/dx dta 2 get dta 0 get sub def /dy dta 3 get dta 1 get sub def
vec 0 dx dta 0 get mul dy dta 1 get mul sub put
vec 1 dx dta 1 get mul dy dta 0 get mul add put
%end vector
/xa dta dsize 4 sub get def /ya dta dsize 3 sub get def
/xb dta dsize 2 sub get def /yb dta dsize 1 sub get def
/dx xb xa sub def /dy yb ya sub def
vec dsize 2 sub dx xb mul put vec dsize 1 sub dy yb mul put
% front distance
/dx dst 2 get def dst dup 0 dx put 1 dx put
% back distance
/dx dst dsize 3 sub get def dst dup dsize 2 sub dx put dsize 1 sub dx put
} bind def
/smoothcurve
{
np
dta 0 get dta 1 get mo
2 2 dsize 1 sub {
/idx ex def
%control point 1
dta idx 2 sub get vec idx 2 sub get dst idx 1 sub get mul add
dta idx 1 sub get vec idx 1 sub get dst idx 1 sub get mul add
%control point 2
dta idx get vec idx get dst idx get mul sub
dta idx 1 add get vec idx 1 add get dst idx get mul sub
%endpoint
dta idx get dta idx 1 add get
curveto } for
} bind def
/curveoffset {
0 2 dsize 1 sub {
/i ex def
dta i dta i get vec i 1 add get cofs sca div mul sub put
dta i 1 add dta i 1 add get vec i get cofs sca div mul add put
} for
} bind def
/DrawCoords
{
gs
/lbl ex def
/sca ex def
/yofs ex def
/xofs ex def
/curv ex def
/ymax -100 def
/ymin 100 def
/ymaxx 0.3 def
/dsize curv length def
xofs yofs tr sca dup scale -90 ro
/chrhgt 0.03125 def
/Helvetica findfont chrhgt scalefont setfont
2 2 dsize 1 sub {
/i ex def
i 1 add curv ex get
dup ymax gt { dup /ymax ex def /ymaxx curv i get def } if
dup ymin lt { dup /ymin ex def } if
pop } for
curv dta copy pop makeopenvectors smoothcurve st smoothcurve cl cp
/stx dta 0 get def /ymax ymax 0.5 add def /ymin ymin 0.5 sub def
np stx 0.5 gt {leading}{trailing}ifelse sca div dup ymax mo ymin li
1 stx 0.5 lt {leading}{trailing}ifelse sca div sub dup ymin li ymax li cl st
np stx 0.5 gt {leading}{trailing}ifelse sca div dup ymax mo ymin li
1 stx 0.5 lt {leading}{trailing}ifelse sca div sub dup ymin li ymax li cl cp
/cofs skin def curveoffset smoothcurve st
curv dta copy pop /cofs skin neg def curveoffset smoothcurve st
ymaxx ymax ymin add 2 div mo
lbl dup stringwidth chrhgt add -2 div ex -2 div ex rm sh
90 ro 1 sca div dup scale xofs neg yofs neg tr gr
} bind def
end
%%EndProlog
%%BeginSetup
AirfoilDict begin
%%EndSetup
$ open/append outfile 'psout'
$ write outfile "/''foiln' ["
$dataloop:
$ read/end_of_file=dataeof infoil inline
$ write outfile inline
$ goto dataloop
$dataeof:
$ close/nolog infoil
$ write outfile " ] def"
$ close/nolog outfile
$!!!!! PLACE NEXT BIT OF POSCRIPT CODE HERE
$ append sys$input 'psout'
% Parameters to DrawCoords are ...
% - array of data to use
% - offset from left edge of paper in inches
% - offset from bottom of paper in inches
% - chord in inches
% - label for the airfoil
%%%% begin first page %%%%
save
72 72 sc % set scale to inches instead of points
0 setlinecap
0 setlinejoin
0.001 setlinewidth
%
% TAKE CARE OF THESE NEXT!!!!
%
%/skin 1 32 div def
%/leading 3 8 div def
%/trailing 0.75 def
$ open/append outfile 'psout'
$ write outfile "/skin ''skint' def"
$ write outfile "/leading ''leade' def"
$ write outfile "/trailing ''traile' def"
$ write outfile " "
$ Ypos = "1.0"
$ LorR = " "
$ desc = "''foiln'@''fsize'in"
$ if scale .nes. "1.0" then desc = desc + " ''scale'%"
$ DRAW = -
"''foiln' ''scale' thickness ''LorR' ''Ypos' 10.75 ''fsize' (''desc') DrawCoords"
$ write outfile DRAW
$ Ypos = "3.0"
$ LorR = "reverse"
$ desc = "''foiln'@''fsize'in"
$ if scale .nes. "1.0" then desc = desc + " ''scale'%"
$ DRAW = -
"''foiln' ''scale' thickness ''LorR' ''Ypos' 10.75 ''fsize' (''desc') DrawCoords"
$ write outfile DRAW
$ write outfile " "
$ write outfile "mirrorpage"
$ write outfile " "
$ Ypos = "1.0"
$ LorR = " "
$ desc = "''foiln'@''fsize'in"
$ if scale .nes. "1.0" then desc = desc + " ''scale'%"
$ DRAW = -
"''foiln' ''scale' thickness ''LorR' ''Ypos' 10.75 ''fsize' (''desc') DrawCoords"
$ write outfile DRAW
$ Ypos = "3.0"
$ LorR = "reverse"
$ desc = "''foiln'@''fsize'in"
$ if scale .nes. "1.0" then desc = desc + " ''scale'%"
$ DRAW = -
"''foiln' ''scale' thickness ''LorR' ''Ypos' 10.75 ''fsize' (''desc') DrawCoords"
$ write outfile DRAW
$
$ close/nolog outfile
$!
$ append sys$input 'psout'
showpage
restore
end
%%Trailer
$ write sys$output "Your Plots are saved in the file: ''psout'"
$ exit
|
| 1113.92 | | HPSPWR::WALTER | | Mon Sep 10 1990 12:27 | 6 |
| Mark,
Nice job on that COM file. Works great! By God, these computers are starting
to actually be USEFUL.
Dave
|
| 1113.93 | Great - now how about... | KAY::FISHER | Stop and smell the balsa. | Mon Sep 10 1990 13:39 | 63 |
| Excellent, Excellent, Excellent.
I played with it a bit and I know it's back in this file
but I can't remember what the use was for the mirror versions
of the airfoils. It seems to me that if you have a left and right
version - you have all the bases covered?
Now - just in case you started to relax in the Fame and Fortune
from this great accomplishment let me lay some additional requests
for future features.
If you ware building a wing with taper you might want to just specify
the root cord and the tip cord and the spacing between ribs.
The program would then calculate the varying cords and spit out the whole
bunch and even number them R1 - through Rn.
Now there are three kinds of simple taper. (1) the leading edge tapers
but the trailing edge is straight (2) the trailing edge tapers but
the leading edge is straight and (3) both the leading and trailing edge
taper. Of course noon of this matters until you start with my next request.
Also there is the variable taper (shulman(sp) plan forms) where you would
specify what rib bay starts the new taper and for how many rib bays this
continues.
I need markings for the wing jig holes! You could ask the diameter of the
holes and the space between holes with the defaults being the standard
Ajusto-Jig sizes. I'll find that out for you if you need the numbers.
Also you then have to think about the vertical taper - that is does the
wing jig hole stay a fixed distance form the bottom of the wing or the
top of the wing or centered?
While were putting a nice wing jig hole on each rib - how about marking the
spar slots. Again there could (should) be a default size spar but you should
be able to specify the spar size for the top and bottom.
If you were to sheet only the center section and not cap the outer ribs then
the center ribs would have the sheeting allowance where as the outer ribs
would not.
Also you may change spar diameters part way down the wing.
Also you may want to leave an additional width for sliding in dihedral
braces both at the center section and at some outboard (polyhedral) position.
Too much for one revision.
OK - first priority is wing jig holes. The criteria for placement is
in the thickest part of the wing but NOT in line with the spar slots
because we want working room for installing spars and shear webs
while on the jig.
But...
If you never do anything else to this program I still say
Excellent, Excellent, Excellent!
Bye --+--
Kay R. Fisher |
---------------O---------------
################################################################################
|
| 1113.96 | Eventually.... | SHTGUN::SCHRADER | | Mon Sep 10 1990 15:33 | 15 |
| I had already thought of adding support in the postscript code for sets of
tapered ribs, spars, etc. I'll add the wing jig holes to my wish list. The bit
about tapered ribs... I don't think that it matters whether the leading edge
or trailing edge is tapered. The chord of the ribs just smoothly decreases
from the root to the tip. Would anybody be interested in a rib set with
an elliptical taper (like a Spitfire)? The tick marks are easy. I assume that
they are for cutting with a bow (couldn't read that reply, only the title). The
reverse image was for ironing the page onto the pattern material. Working these
mods in is going to take a while but I've figured out how to do them and still
keep the code fairly clean. Another thing that I'm thinking about is adding
support for smooth closed curves. Airfoils are open curves. They start at the
trailing edge and end at the trailing edge. A closed curve would be more like
a fuse former, it doesn't really have a starting point and ending point.
Glenn Schrader
|
| 1113.97 | My Reply Was Blown Away... | CLOSUS::TAVARES | John--Stay Low, Keep Moving! | Mon Sep 10 1990 18:30 | 26 |
| Sorry about that; WEWAND decided to go south at a critical moment
and I actually thought it blew away my whole reply...looks like
the title only survived.
Lesse...what did I have in that note? On the tick marks, yes,
you guessed correctly, that they would be used in bow cutting,
though they would be useless for those using an automatic
machine.
Oh yes, on Kay's comment about the reversed/mirror foil. I had
asked Glenn offline to put the reversed foil in to use on the
opposite end of a foam block. I don't know what the mirrored
image would be used for.
Also, on my comment that I didn't understand why Glenn had us
specify the skin thickness, foil thicknes, etc on the second page
separately. You answered that Kay: because the outer foil may be
different than the inner one. Thanks.
Glenn: is the curve-fitter working properly? I did my Clark_Y
with the extra data points that I had previously put in at 1/32,
1/16, and I think, 1/64. Just out of curiousity I commented
those points in, leaving the 1/8 inch point from the original
listing as the first point. The result was a perfectly straight
line from the origin to the 1/8 point, implying that the
curve-fitter was not working.
|
| 1113.98 | more on jig holes | KAY::FISHER | Stop and smell the balsa. | Mon Sep 10 1990 18:30 | 16 |
| >I had already thought of adding support in the postscript code for sets of
>tapered ribs, spars, etc. I'll add the wing jig holes to my wish list. The bit
>about tapered ribs... I don't think that it matters whether the leading edge
>or trailing edge is tapered. The chord of the ribs just smoothly decreases
>from the root to the tip.
It matters when you put jig holes and/or spar notches in the ribs!
In fact I have been unable to use my jig on some previous kits because
I couldn't figure out where to put the holes. An interesting case that
the jig can't handle (some would argue that it can if you mount all the
ribs at an angle) is swept back wings (like an Aeromaster Bipe).
Bye --+--
Kay R. Fisher |
---------------O---------------
################################################################################
|
| 1113.99 | Airfoil table...how do you read it??? | AKOV11::COLLINS | | Tue Sep 11 1990 20:52 | 16 |
| Can someone help me inturppet an airfoil table. Here is what it looks like;
---------------------------------------------------------------------------------------
% | 0 |1.25|2.5 |5.0|7.5|10 | 15 | 20 | 30 | 40 | 50 | 60 |65 |70 |80 | 90 |95 |100
---------------------------------------------------------------------------------------
upr|3.5|5.5 |6.5 |7.9|8.8|9.6|10.68|11.36|11.7|11.4|10.52|9.15|8.3|7.4|5.6| 3.8|2.9|2.0
---------------------------------------------------------------------------------------
lwr|3.5|1.93|1.47|.93|.63|.42|.375 | .03 | 0 | 0 | 0 | 0 | 0 |.06|.38|1.02|1.4|1.85
can someone help me?
Norm
|
| 1113.100 | Airfoil table interpretation | GENRAL::KNOERLE | | Tue Sep 11 1990 23:27 | 35 |
| Norm,
the upper row with the percentage numbers is the percentage of your
wing width. Assume your wing would be 10 inch wide, 1.5 % would be
0.15 inch from the leading edge. 5% would be 1/2 inch, 20 % would be
2 inch etc.
The two rows below describe the upper and lower part of the airfoil.
Connect all points of the upr values and you will get the shape of the
top half of the airfoil. Do the same with the lower part.
The numbers are also percentage of your airfoil length (I believe)
This airfoil will have around 12 % thickness. Each point is calculated
the same way as described above.
%
10 |
8 |
6 | _-------------_________
4 | / ---------_____
2 |/ -----____
0 +-------------------------------------------========
-2 |\__________________________----------------
-4 |
-6 | (can you imagine this beeing an airfoil ? )
-8 |
+---------------------------------------------------------------
0 10 20 30 40 50 60 70 80 90 100 percentage of
airfoil
Your airfoil should come out somehow like this.
Refer Notes 1113.61, 1113.87 or 1113.17 for a superb airfoil-
program written by Glen Schrader.
Holm- und Rippenbruch, Bernd
|
| 1113.101 | More on wing sections | GIDDAY::CHADD | | Wed Sep 12 1990 06:18 | 25 |
| Re : Airfoil table...how do you read it???
Norm,
Its quite simple really;
--------------------------
% | 0 |1.25|2.5 |5.0|7.5| <-- these numbers are points based on the % of the
-------------------------- wing cord. (eg: a 10" wing cord position 1.25
is .125" from the leading edge, 2.5 = .25" etc)
upr|3.5|5.5 |6.5 |7.9|8.8| <-- These are positions above and below the
-------------------------- reference line of the wing (not the camber
lwr|3.5|1.93|1.47|.93|.63| line) as a % of the wing cord (eg: 3.5 = .35",
1.93 = .193", however -1.93 = .193" below the
reference line.. etc..)
Note the cord is the width of the wing, tapered wings have multiple cords and
each template will be different.
If you see Nose Radius specified this also refers to the cord (eg: 1% Nose
Radius = .1" Radius on the leading edge)
Hope this helps.
John
|
| 1113.102 | *.FOIL file problems | SHTGUN::SCHRADER | | Wed Sep 12 1990 17:43 | 65 |
|
RE the previous notes about the non-round leading edge. I've found some
problems in a few of the .FOIL files. The problem is that some of the coordinate
arrays go from leading edge to the trailing edge then back to the leading edge.
For example:
0.00 0.00 %leading edge
0.25 0.10
etc
1.00 0.00 %trailing edge
etc
0.00 0.00 %leading edge again
The smoothing algorithm expects the coordinates to go from trailing edge to
the leading edge then back to the trailing edge:
1.00 0.00 %trailing edge
more %upper surface coordinates
0.00 0.00 %leading edge
more %lower sufface coordinates
1.00 0.00 %trailing edge again
The algorithm interprets the coordinate array as an open curve and does not
try to curve around the trailing edge. This is why the trailing edge needs to
be at the start and end of the file. The program also uses this as an
assmumption to figure out where to place the leading and trailing edge
graphics. This is why some plots seemed to have the leading and trailing edge
dimensions reversed.
Another thing to watch out for is repeated points. As an example say that the
points for the upper surface end on the leading edge at 0.00 0.00 and the
points for the lower surface start off at 0.00 0.00 then go to the trailing
edge. The repeated point will show up as a "corner" rather than a smooth
curve. This will actually be handy for some enhancements that i've been
thinking about.
Anyway, the coordinates in all of the FOIL files should start at the trailing
edge, follow the upper surface to the leading edge, then follow the lower
surface back to the trailing edge. This wasn't a problem when the program was
drawing straight lines but it makes a difference to the smoothing algorithm.
It's also a good idea to make the first and last points in the array identical
(i.e. the aft most point on the trailing edge).
To re-arrange the .FOIL files, get a copy of the file:
SHTGUN:[PUBLIC.RC]AFCVT.COM
This com procedure rearranges properly formatted .FOIL files. It assumes that
the file is formatted as follows:
- one or more blank lines or comments
- the upper surface coordinates with no embedded lines that do not
start with a digit (comments on the end of lines are OK).
- one or more comment lines (with marks the start of the lower surface
data
- and finally the block of lower surface points.
To use the .COM file use the following command:
@AFCVT <inputfile> <outputfile>
After re-formatting the .FOIL file it is usually necessary to remove a
repeated point at the leading edge.
Glenn Schrader
|
| 1113.103 | Incomplete filespec | SHTGUN::SCHRADER | | Thu Sep 13 1990 12:37 | 5 |
| The .COM file that I mentioned in the previous note can be found at:
SHTGUN::DUA1:[PUBLIC.RC]AFCVT.COM not SHTGUN::[PUBLIC.RC]AFCVT.COM
G. Schrader
|
| 1113.104 | ONE MORE TIME..... | SHTGUN::SCHRADER | | Fri Sep 14 1990 20:16 | 30 |
| Well, folks. I got a text library version of the command procedure and
postscript working. It turned out to be easier than I thought it would be.
To try it out get a copy of the file at:
SHTGUN::DUA1:[PUBLIC.RC]AIRFOIL_V31.TLB
After you have then then execute the following command to extract the command
procedure from the library file:
LIBR/TEXT AIRFOIL_V31.TLB/EXTRACT=$AIRFOIL_V31/OUTPUT=AF31.COM
The command procedure will be in AF31.COM (or whatever you called it) so just
do an @AF31 to start it. The AIRFOIL_V31.TLB file must be in the default
directory when you run AF31. The command procedure runs pretty much the
same as the original with a couple of exceptions. When it starts up it will
display a list of airfoils which are in the library. To select one of them
just enter it. You can still use any FOIL files that are laying around by
prefixing the name with an "@". If, for instance, you have a file named
MYFOIL.FOIL then to use it enter @MYFOIL at the airfoil name prompt. A blank
airfoil name shows a directory of all of the FOIL files which are available
as separate files. A single question mark re-prints the airfoil entries
which are available in the text library. Another change which I made is that
the prompts for the leading edge, trailing edge and skin thickness will now
accept fractional values. For instance, a skin with a thickness of one
sixteenth could be entered as either 1/16 or 0.0625 . I've also cleaned up
the airfoil coordinate entries which are in the text library.
Enjoy,
G. Schrader
|
| 1113.105 | Bug in V3.1... | ROCK::MINER | Dan Miner, DTN:225-4015, HLO2-3/D11 | Fri Sep 14 1990 20:48 | 13 |
| There is a bug in this. I have notified Glenn and I assume it will
be trivial to fix. Stand by for a fixed version...
_____
| \
| \ Silent POWER!
_ ___________ _________ | Happy Landings!
| \ | | | | |
|--------|- SANYO + ]-| ASTRO |--| - Dan Miner
|_/ |___________| |_________| |
| / | " The Earth needs more OZONE,
| / not Caster Oil!! "
|_____/
|
| 1113.106 | An impossible wish? | CURIE::ANKER | Anker Berg-Sonne | Sat Sep 15 1990 18:57 | 12 |
| I have been reluctant to ask for this, but boy would it
be great!
Often I want to create an airfoil for a balsa sheeted
foam wing. To get the accurate airfoil, the template should not
include the thickness of the sheeting. What I would like is for
an option in the airfoil program to draw both the airfoil and a
line a given thickness inside, normally 1/16!
How about that?
Anker
|
| 1113.107 | Oh Yes It Does! | CLOSUS::TAVARES | John--Stay Low, Keep Moving! | Mon Sep 17 1990 14:05 | 5 |
| Anker, you haven't had your coffee yet this morning; I can tell!
Please re-check the program notes, it indeed does allow you to
specify sheeting thickness, and it draws the sheeting line very
nicely inside the foil.
|
| 1113.108 | One more, One more time... | SHTGUN::SCHRADER | | Mon Sep 17 1990 17:07 | 3 |
| The fix is in! Have at it!
Glenn Schrader
|
| 1113.109 | naca6409.foil | CLOSUS::TAVARES | John--Stay Low, Keep Moving! | Mon Oct 01 1990 15:02 | 50 |
| Here's a little gem of an undercambered airfoil for free
flight/glider applications. Its not a Selig, but its a goodie.
As usual, the nose is a little rough; still haven't got the hang
of it.
%naca6409
%topside
1.00000 0.00090
%.95000 0.00000
0.90000 0.02950
0.80000 0.05340
0.70000 0.07280
0.60000 0.08780
0.50000 0.09810
0.40000 0.10350
0.30000 0.10130
0.25000 0.09650
0.20000 0.08880
0.15000 0.07780
0.10000 0.06310
0.07500 0.05420
0.05000 0.04300
0.02500 0.02960
0.01250 0.02060
%.00620 0.04750 %I added this
%.00310 0.04200 %ditto
0.00000 0.00000
%underside
0.00000 0.00000
%.00150 0.02900 %ditto
%.00310 0.02750 %ditto
%.00620 0.02400 %ditto
0.01250 -0.00880
0.02500 -0.01110
0.05000 -0.01180
0.07500 -0.01080
0.10000 -0.00880
0.15000 -0.00360
0.20000 0.00170
0.25000 0.00690
0.30000 0.01120
0.40000 0.01650
0.50000 0.01860
0.60000 0.01980
0.70000 0.01760
0.80000 0.01360
0.90000 0.00740
%.95000 0.00000
1.00000 0.00090
|
| 1113.110 | SD7032 | ELMAGO::TTOMBAUGH | High Plains Drifter | Fri Oct 05 1990 17:51 | 69 |
| Quoted from Soartech #8 :
The SD7032 is among the best of the thermal-duration type airfoils
(such as the Aquila, E214, S2091, S4061, SD6080. The design of this
new airfoil incorporates what is presently known about mitigating
laminar separation problems through the use of a bubble ramp.
1.00000 0.00000
0.99674 0.00048
0.98712 0.00204
0.97155 0.00485
0.95054 0.00894
0.92464 0.01420
0.89436 0.02041
0.86021 0.02731
0.82264 0.03460
0.78208 0.04199
0.73892 0.04925
0.69356 0.05620
0.64646 0.06270
0.59812 0.06861
0.54902 0.07381
0.49967 0.07816
0.45058 0.08154
0.40222 0.08385
0.35506 0.08500
0.30953 0.08493
0.26604 0.08359
0.22499 0.08096
0.18671 0.07703
0.15146 0.07182
0.11948 0.06548
0.09105 0.05809
0.06627 0.04976
0.04524 0.04078
0.02812 0.03145
0.01502 0.02206
0.00606 0.01293
0.00115 0.00448
0.00038 -.00223
0.00532 -.00701
0.01649 -.01088
0.03308 -.01403
0.05491 -.01635
0.08180 -.01787
0.11351 -.01862
0.14974 -.01867
0.19010 -.01810
0.23420 -.01699
0.28153 -.01547
0.33154 -.01363
0.38364 -.01152
0.43724 -.00922
0.49176 -.00678
0.54659 -.00430
0.60112 -.00190
0.65469 0.00030
0.70664 0.00224
0.75634 0.00379
0.80313 0.00485
0.84635 0.00535
0.88534 0.00526
0.91942 0.00458
0.94797 0.00350
0.97054 0.00226
0.98684 0.00113
0.99670 0.00030
1.00001 0.00000
|
| 1113.111 | oh, for a SD7037 (with attachments) for Christmas | BRAT::RYDER | perpetually the bewildered beginner | Sat Oct 06 1990 01:15 | 20 |
| In the September 90 issue of R/C Soaring Digest (page 12), Bob Dodgson
writes about the SD7037 and its use in his new Saber.
"SD7037 .. nearly matches the minimum sinking speed of the tripped E214
and offers at least as good a maximum L/D. ..... the SD7037 offers even
better performance at the high speed end. In fact, the SD7037 offers
high speed performance that nearly matches the faster sinking airfoils
designed primarily for high speed performance like the S3021.
".... it appears that with 2 to 3 degrees of reflex, the SD7037 will
match the high-end performance of the thicker and less versatile S3021
and it clearly leaves the SD7032 in the dust. It also appears that
with 2 to 3 degrees of positive camber, the SD7037's minimum sinking
speed can be improved. ....
.
.
"Since the SD7037 airfoil is very thin (9.2 percent thick) we have had
to employ carbon fiber in the spar ..... foam ... Obechi ..."
|
| 1113.112 | HELP... (please) | MJBOOT::BENSON | __Frank Benson, DTN 348-4944__ | Mon Oct 08 1990 12:41 | 13 |
| I extracted 1113.10, removed the header info and named it SD7037.FOIL.
When I invoke the postscript airfoil program, I get a listing of the
internal foils. When I press return, I get the SD7037 listing.
However, if I type SD7037 or SD7037.FOIL, the program comes back with a
foil not found error.
What am I missing here? (other than my mind...)
THANKS-
__|__ Regards-
\________________________O________________________/ Frank.
|
| 1113.113 | | ELMAGO::TTOMBAUGH | High Plains Drifter | Mon Oct 08 1990 12:58 | 11 |
| re .112
uummm...if you're referring to note .110, that's an SD7032 foil.
IF I get time this week I'll enter the SD7037 coordinates as well
as the SD8020 stabilator foil.
IMHO the 7032 will work better for most thermal duration flying
without having to use flaps. Thats why I entered it first, as well
as needing to have a template to cut cores this week.
Terry
|
| 1113.114 | A rose by any other name... | MJBOOT::BENSON | __Frank Benson, DTN 348-4944__ | Mon Oct 08 1990 13:51 | 9 |
| Terry-
You're right, but even when I change the name of the file to 7032, I
still have the problem in .112. Any ideas?
__|__ Regards-
\________________________O________________________/ Frank.
|
| 1113.115 | It worked for me | ELMAGO::TTOMBAUGH | High Plains Drifter | Mon Oct 08 1990 15:25 | 7 |
| I can't see where you're doing anything wrong in .112. My only guess
is that something went wrong when you removed the headers from my
original note in .110. There can't be anything in the file above
the two columns of numbers.
Terry
|
| 1113.116 | It worked with "@name.FOIL" for me... | GENRAL::KNOERLE | | Mon Oct 08 1990 15:35 | 5 |
| I had the same trouble with calling an airfoil that was not listed.
Just add @name.foil and it worked.
Bernd
|
| 1113.117 | Mystery Solved! | MJBOOT::BENSON | __Frank Benson, DTN 348-4944__ | Mon Oct 08 1990 15:51 | 12 |
| Bernd-
That's right! I just took a look at the PS code and reasoned that it
was looking for "@" in front of the name. (Not bad for a salesman,
eh?) I tried it and it worked fine. I was just about to enter a note
to that effect.
THANKS for your reply!
__|__ Regards-
\________________________O________________________/ Frank.
|
| 1113.118 | Reply from the designer... | SHTGUN::SCHRADER | | Mon Oct 08 1990 16:47 | 14 |
| I haven't looked in here for a couple of days so the other guys beat me to it.
The @ prefix is what tells the program to scan the directory for a .FOIL file
rather than to look for it in the airfoil library. If you wish, you can add the
airfoil to your library using the following command
$LIBR/INSERT AIRFOIL_V31.TLB/TEXT <FOIL FILE NAME>
The only problem with this is that you would have to do this for every release
of the program. Tell ya what. If anybody has airfoils that they would like to
have included in the master library then mail them to me at SHTGUN::SCHRADER.
One airfoil per mailing please but send as may as you want. I'm probably going
to do another release within a week or two.
Glenn Schrader
|
| 1113.119 | SD8020 | ELMAGO::TTOMBAUGH | High Plains Drifter | Tue Oct 09 1990 16:37 | 66 |
| Selig designed this symmetrical 'foil as an improvement to the
NACA0009, for stabilator use. He claims a lower deadband. At 10%
thickness it has plenty of room for large pivot tubes.
1.00000 0.00000
0.99646 0.00027
0.98625 0.00131
0.97017 0.00330
0.94885 0.00591
0.92247 0.00876
0.89118 0.01188
0.85538 0.01532
0.81560 0.01908
0.77237 0.02308
0.72627 0.02722
0.67789 0.03135
0.62777 0.03535
0.57647 0.03909
0.52456 0.04246
0.47261 0.04536
0.42116 0.04770
0.37077 0.04938
0.32196 0.05034
0.27523 0.05051
0.23106 0.04982
0.18987 0.04824
0.15203 0.04574
0.11789 0.04233
0.08774 0.03802
0.06179 0.03287
0.04024 0.02697
0.02318 0.02041
0.01065 0.01345
0.00276 0.00645
0.00000 0.00000
0.00276 -.00645
0.01066 -.01345
0.02319 -.02041
0.04024 -.02697
0.06180 -.03287
0.08774 -.03802
0.11790 -.04233
0.15204 -.04574
0.18987 -.04824
0.23107 -.04982
0.27524 -.05051
0.32197 -.05034
0.37077 -.04938
0.42117 -.04769
0.47262 -.04536
0.52457 -.04246
0.57648 -.03908
0.62778 -.03534
0.67790 -.03135
0.72629 -.02722
0.77238 -.02308
0.81561 -.01907
0.85539 -.01532
0.89119 -.01188
0.92248 -.00876
0.94886 -.00591
0.97018 -.00330
0.98626 -.00131
0.99647 -.00027
1.00001 0.00000
|
| 1113.120 | S3014 | SOLKIM::BOBA | Bob Aldea @PCO | Fri Oct 19 1990 17:09 | 70 |
| % Similar to the S3021, it has lift and drag characteristics similar to
% the E193 and E205 but is improved in drag. Better than the S3010 or
% S3021 at very low Reynolds numbers (down to 60,000). Ideal for wing
% tips or HLGs. Falcon 880 uses a S3021 for the root to the tip panel
% and the S3014 for the tip panel itself.
/S3014 [
1.00000 .00000
.99663 .00021
.98667 .00099
.97044 .00264
.94840 .00532
.92108 .00911
.88906 .01394
.85297 .01970
.81342 .02617
.77104 .03310
.72642 .04012
.68001 .04685
.63214 .05301
.58321 .05850
.53368 .06322
.48405 .06704
.43477 .06988
.38629 .07166
.33908 .07235
.29354 .07192
.25001 .07043
.20924 .06790
.17136 .06434
.13682 .05971
.10585 .05403
.07864 .04741
.05535 .03997
.03607 .03190
.02088 .02344
.00978 .01492
.00278 .00682
.00000 -.00003
.00284 -.00526
.01183 -.00972
.02610 -.01383
.04545 -.01731
.06973 -.02006
.09879 -.02204
.13239 -.02329
.17024 -.02386
.21197 -.02385
.25713 -.02335
.30520 -.02244
.35564 -.02120
.40787 -.01970
.46129 -.01801
.51527 -.01620
.56920 -.01433
.62242 -.01246
.67431 -.01064
.72423 -.00893
.77158 -.00736
.81577 -.00595
.85625 -.00472
.89250 -.00367
.92405 -.00277
.95049 -.00199
.97151 -.00124
.98699 -.00052
.99668 -.00010
1.00001 .00000
] def
|
| 1113.121 | SS7084 | BARNA::JORDI | | Mon Nov 26 1990 14:23 | 70 |
| In the next page follows the SD7084 coordinates. It has good low speed
characteristics.
Regards.
Jordi
%SD7084
1.00000 0.0
0.99658 0.00030
0.98650 0.00139
0.97026 0.00361
0.94845 0.00706
0.92172 0.01163
0.89064 0.01708
0.85575 0.02311
0.81748 0.02938
0.77619 0.03557
0.73218 0.04152
0.68584 0.04716
0.63770 0.05245
0.58829 0.05727
0.53815 0.06151
0.48783 0.06508
0.43785 0.06786
0.38874 0.06978
0.34098 0.07074
0.29505 0.07068
0.25139 0.06955
0.21042 0.06734
0.17254 0.06399
0.13804 0.05945
0.10710 0.05374
0.07986 0.04698
0.05642 0.03934
0.03687 0.03109
0.02132 0.02256
0.00985 0.01413
0.00263 0.00631
0.00000 -.00016
0.00294 -.00551
0.01167 -.01031
0.02575 -.01440
0.04512 -.01786
0.06955 -.02071
0.09876 -.02295
0.13245 -.02458
0.17030 -.02560
0.21190 -.02607
0.25680 -.02601
0.30452 -.02547
0.35455 -.02448
0.40633 -.02312
0.45931 -.02143
0.51289 -.01951
0.56647 -.01741
0.61943 -.01520
0.67116 -.01298
0.72105 -.01079
0.76852 -.00873
0.81296 -.00685
0.85379 -.00522
0.89047 -.00384
0.92250 -.00272
0.94942 -.00182
0.97088 -.00105
0.98671 -.00039
0.99661 -.00006
1.00000 0.00000
|
| 1113.122 | Isn't Postscript wonderful | ZENDIA::REITH | Jim Reith DTN 226-6102 - LTN2-1/F02 | Tue Nov 27 1990 12:23 | 10 |
| Just got a chance to try out this stuff. Wow! It caused our LPS40 a
little heartburn but it finally burped them out. This combined with the
automatic foam cutter will be dynomite. I'm planning on trying a S3014
foam wing on the Gnome to try to improve penetration over the standard
12% S205.
Anybody got a good 2-meter airfoil suggestion to take advantage of the
addition of reflex flaps (I've heard that some it makes a big difference
and on others you don't notice it) This would go on a Gentle Lady size
fuselage.
|
| 1113.123 | Simplex 7% | CLOSUS::TAVARES | John--Stay Low, Keep Moving! | Wed Dec 05 1990 20:28 | 23 |
| Here's one for the indoor crowd:
%Simplex 7%
%topside
1.00 0.000
0.95 0.0093
0.90 0.0181
0.80 0.0342
0.70 0.0476
0.60 0.0583
0.50 0.0658
0.40 0.0696
0.30 0.0689
0.25 0.0664
0.20 0.0622
0.15 0.0557
0.10 0.0462
0.075 0.0399
0.05 0.0320
0.025 0.0216
0.0125 0.0144
0.000 0.000
1.00 0.000
|
| 1113.124 | E374 coordinates | GAUDI::EDO | | Wed Dec 19 1990 11:43 | 76 |
|
Hi all,
Attached a more accurate set of coordinates for an Eppler 374 airfoil.
Enjoy it.
Merry X'mas for all
Jordi
%Eppler E-374 from Flug-und Modelltechnik August 1990 pg. 17
1.000000 0.000000
0.996400 0.000450
0.986100 0.002040
0.970000 0.004850
0.948640 0.008460
0.922140 0.012640
0.890780 0.017470
0.855080 0.022970
0.815600 0.029050
0.772930 0.035600
0.727690 0.042460
0.680530 0.049440
0.632100 0.056290
0.583090 0.062690
0.533980 0.068210
0.485110 0.072520
0.436820 0.075440
0.389390 0.076850
0.343120 0.076700
0.298240 0.075070
0.255100 0.072170
0.214150 0.068170
0.175830 0.063190
0.140530 0.057340
0.108600 0.050730
0.080360 0.043510
0.056050 0.035810
0.035890 0.027810
0.020040 0.019730
0.008620 0.011860
0.001780 0.004590
0.000000 0.000000
0.000140 -0.001210
0.004370 -0.006220
0.014270 -0.011300
0.029350 -0.016000
0.049490 -0.020150
0.074540 -0.023690
0.104280 -0.026600
0.138450 -0.028900
0.176690 -0.030600
0.218610 -0.031750
0.263740 -0.032380
0.311580 -0.032550
0.361590 -0.032280
0.413200 -0.031630
0.465800 -0.030640
0.518770 -0.029310
0.571500 -0.027670
0.623360 -0.025690
0.673820 -0.023330
0.722430 -0.020590
0.768730 -0.017600
0.812280 -0.014500
0.852540 -0.011530
0.888920 -0.008820
0.920850 -0.006430
0.947830 -0.004320
0.969580 -0.002410
0.985940 -0.000910
0.996370 -0.000160
1.000000 0.000000
|
| 1113.125 | New release of the airfoil library & postscript generator. | SHTGUN::SCHRADER | | Wed Dec 19 1990 20:19 | 24 |
| Like the title says, i've got a new release of the program working. To get
a copy just enter the command:
$ COPY SHTGUN""::DUA1:[PUBLIC.RC]AIRFOIL_V32.* []
This will produce two files:
AIRFOIL_V32.README
AIRFOIL_V32.TLB
The .README file says how the extract the .COM file from the .TLB and explains
the prompts. The new features are:
Rib sets with either straight or elliptical taper
NACA 4 digit airfoils
Wing jig hole placement with adjustable washout/washin, taper, etc
Multiple copies
Draft mode
The .README describes this stuff so I won't repeat it here.
Enjoy,
G. Schrader
|
| 1113.127 | the bug in V32a has been fixed | SHTGUN::SCHRADER | | Thu Dec 20 1990 14:51 | 3 |
| It should be OK now.
Glenn
|
| 1113.128 | AF32.COM | GAUDI::EDO | | Thu Dec 27 1990 08:27 | 16 |
| Hi Glenn,
I think there are some bugs in the command procedure AF32.COM
It is not possible to select one of the listed profiles, the answer when
I try is:
%DCL-W-ABVERB, ambiguous command verb - supply more characters
\W\
Regards.
Jordi (ex BARNA::JORDI)
|
| 1113.129 | Known bug... | SHTGUN::SCHRADER | | Thu Dec 27 1990 16:20 | 13 |
| Yep, that's a bug all right. There are two ways to get things working.
Either:
- get a copy of the latest file (same place, same filename)
- define a global symbol W as follows:
$ W:==WRITE SYS$OUTPUT
The version of the .COM file in the latest library uses real WRITE SYS$OUTPUTs
instead of Ws.
G. Schrader
|
| 1113.130 | SD7037.FOIL | POBOX::KAPLOW | Set the WAYBACK machine for 1982 | Thu Dec 27 1990 16:27 | 67 |
| No one has posted it before, so here is the SD7037.
%Selig SD7037 from Soartech #8
%upper surface
1.00000 0.00000
0.99672 0.00042
0.98707 0.00180
0.97146 0.00436
0.95041 0.00811
0.92450 0.01295
0.89425 0.01865
0.86015 0.02490
0.82261 0.03141
0.78201 0.03788
0.73865 0.04413
0.69294 0.05011
0.64539 0.05572
0.59655 0.06085
0.54693 0.06538
0.49706 0.06917
0.44745 0.07211
0.39862 0.07410
0.35101 0.07504
0.30508 0.07488
0.26125 0.07358
0.21989 0.07113
0.18137 0.06754
0.14601 0.06286
0.11410 0.05715
0.08586 0.05049
0.06146 0.04300
0.04102 0.03486
0.02462 0.02632
0.01232 0.01770
0.00418 0.00936
0.00021 0.00185
%lower surface
0.00126 -0.00393
0.00806 -0.00839
0.02038 -0.01227
0.03800 -0.01541
0.06074 -0.01777
0.08844 -0.01934
0.12084 -0.02017
0.15765 -0.02032
0.19850 -0.01987
0.24296 -0.01891
0.29005 -0.01754
0.34071 -0.01586
0.39288 -0.01396
0.44643 -0.01190
0.50074 -0.00976
0.55519 -0.00760
0.60914 -0.00549
0.66197 -0.00349
0.71307 -0.00168
0.76178 -0.00014
0.80752 0.00104
0.84964 0.00182
0.88756 0.00220
0.92071 0.00218
0.94859 0.00185
0.97077 0.00132
0.98690 0.00071
0.99671 0.00021
1.00001 0.00000
|
| 1113.131 | another "feature" | POBOX::KAPLOW | Set the WAYBACK machine for 1982 | Thu Dec 27 1990 16:32 | 6 |
| Another "feature" I just found: the foil names seem to be case
sensitive. The procedure barfed on sd7003, but accepted SD7003
without error. When you get a chance... I also posted the sd7037,
as noone else has done so, to include in the next revision. One of
these days I will unpack my papers and find the Stalick "Darn Good
Airfoil" booklet.
|
| 1113.132 | possible enhancements to V3.2 | POBOX::KAPLOW | Set the WAYBACK machine for 1982 | Thu Dec 27 1990 18:06 | 29 |
| Some additional comments on V3.2: It seems "slow" in starting up.
I assume that there is significant initialization that is
happening. It would save some time if you could put a loop in the
code, so that I can generate several airfoils without repeating
unnecessary code. If they could all be written to a single output
file, it might also save some printing (or at least comm line)
time.
Now that you have included the NACA airfoil generator, you could
delete the old definitions of NACA airfoils that the generator
replaces from the library. BTW, I looked at the code in $NACA, but
didn't understand it at all. Where did you find the NACA
algorithms? I'd like to understand how they are generated. Have
the numbers generated been checked against the "known" airfoils
that we have so far? I have some bizare related needs, so the
ability to scale to a power, rather than a multiple might be
useful. I'm looking to build a low drag laminar flow body for some
of my model rockets, and was told to scale a symmetric airfoil of
choice to the 3/2 power.
Also on the subject of cleanup, I seem to have lost the HQ2509,
thus you never picked it up from my "library". I think I have it
at home. I thought that the HQ25xx and HQ15xx are simple scalings
of each other, but in checking the numbers, it doesn't seem to be
so. Anyone know more about the HQ series?
Anyone know where I can buy a postscript driven milling machine to
free some wings from the balsa and/or foam blocks they are trapped
in :-)
|
| 1113.133 | Rampant Featureitis | SHTGUN::SCHRADER | | Thu Dec 27 1990 20:33 | 40 |
| RE -.1
It starts up slow because it's building the display list of airfoils in the
library. Looping back to the airfoil prompt is easy, is on the wish list.
I was initially going to get rid of the NACA files in the library but deceded
to keep them in case the NACA generator started breaking for some reason.
Many thanks to John Tavares, who sent me a Model Aviation article (November
1984) on how to generate NACA airfoils. I'm not surprised that you can't
follow the code. Normal PostScript is cryptic enough but this number
crunching stuff is simply too much. What it is doing is actually pretty
straightforward. The main part of the airfoil is defined by a fixed thickness
distribution and a variable mean line. The camber and point of maximum camber
define the shape of the mean line. The thickness distribution defines points
at equal distances above and below the mean line. This was easy enough. The
hair pulling part was the leading edge (radius = 1.1 * square of thickness).
A lot of the wierd code is calculating a curve that blends the round leading
edge into the thickness distribution in a way that looks "natural". This
changes every time since the height of the thickness distribution is directly
proportional to the thickness while the leading edge radius is proportional to
the square of the thickness. If you are drawing out airfoils by hand then the
blending is easy. Just pull out the french curve and draw in something that
looks right. It's tougher when you have to actually calculate out the points.
The generator produces airfoils that have the leading edge shaped a little
differently than the airfoils that were in the library but the shapes that
i'm getting are as good as I could have done by hand so I'm not sure if it
really makes a difference. As a side note, some future rev may
also support the 5 and/or 6 digit airfoil series. This won't happen very
quickly (that annoying work stuff, don't ja know 8^).
The non-linear scaling is an interesting problem. The easiest way would be
to modify the thickness procedure to scale the airfoil data array differently.
I'll post something on how to patch the procedure (probably next week).
I'm curious as to why you would want to scale like this though. It seems to
me that if you start off with a laminar flow airfoil and scale it non-linearly
then it will probably wind up non-laminar since the profile changes. Maybe it's
because a wing is expanding the airflow in 1 dimension while a nosecone expands
the airflow in 2 dimensions?
G. Schrader
|
| 1113.134 | enter a new dimension | POBOX::KAPLOW | Set the WAYBACK machine for 1982 | Fri Dec 28 1990 15:06 | 17 |
| Thanks. I've got MA way back (I think I missed the first 12 issues
after they went on their own back in 75-76), so I can dig out the
article and read it myself.
|I'm curious as to why you would want to scale like this though. It seems to
|me that if you start off with a laminar flow airfoil and scale it non-linearly
|then it will probably wind up non-laminar since the profile changes. Maybe it's
|because a wing is expanding the airflow in 1 dimension while a nosecone expands
|the airflow in 2 dimensions?
That's exactly how it was explained to me. The friend in question
just quit working at the Skunkworks, and was part of the team that
designed and built the Dedaelus, so I have to assume he knows what
he's talking about. The resulting shapes look pretty wierd, but if
the air is happy, and the drag is reduced, I can live with the
looks.
|
| 1113.135 | HQ-2.5/9 | POBOX::KAPLOW | Set the WAYBACK machine for 1982 | Tue Jan 01 1991 20:18 | 43 |
| %Quabeck HQ-2.5/9 from 10/83 Soaring Flight
%upper surface
0.000000 0.000000
0.005000 0.009100
0.012500 0.014800
0.025000 0.023200
0.050000 0.033900
0.100000 0.047500
0.150000 0.056000
0.200000 0.061700
0.250000 0.065300
0.300000 0.067600
0.350000 0.069000
0.400000 0.068600
0.500000 0.065800
0.600000 0.058500
0.700000 0.047200
0.800000 0.032900
0.850000 0.024900
0.900000 0.016900
0.950000 0.008100
1.000000 0.000000
%lower surface
1.000000 0.000000
0.950000 0.002200
0.900000 0.003100
0.850000 0.003000
0.800000 0.001700
0.700000 -0.003200
0.600000 -0.010000
0.500000 -0.015800
0.400000 -0.019700
0.350000 -0.021000
0.300000 -0.021200
0.250000 -0.021300
0.200000 -0.020600
0.150000 -0.019800
0.100000 -0.017500
0.050000 -0.014300
0.025000 -0.011000
0.012500 -0.008000
0.005000 -0.004500
0.000000 0.000000
|
| 1113.136 | HQ15-85 | GAUDI::EDO | | Wed Jan 02 1991 14:30 | 49 |
|
Hi all,
Another good F3B profile for machines about 3.0 meters of span.
Regards.
Jordi
%Quabeck HQ-15-85 from 3/88 Flug und Modelltechnik
1.000000 0.000000
0.950000 0.005700
0.900000 0.011700
0.850000 0.018100
0.800000 0.024200
0.700000 0.037000
0.600000 0.046900
0.500000 0.053600
0.400000 0.056500
0.350000 0.056800
0.300000 0.056100
0.250000 0.054600
0.200000 0.051800
0.150000 0.047500
0.100000 0.040300
0.050000 0.028900
0.025000 0.020100
0.012500 0.014200
0.005000 0.008300
0.000000 0.000000
0.005000 -0.006400
0.012500 -0.010100
0.025000 -0.013800
0.050000 -0.018400
0.100000 -0.024300
0.150000 -0.027500
0.200000 -0.029000
0.250000 -0.029600
0.300000 -0.029400
0.350000 -0.028800
0.400000 -0.027700
0.500000 -0.023700
0.600000 -0.017800
0.700000 -0.010600
0.800000 -0.003500
0.850000 -0.001600
0.900000 -0.000300
0.950000 0.000300
1.000000 0.000000
|
| 1113.137 | Found: Stalick's Darn Good Airfoils #3 | POBOX::KAPLOW | Set the WAYBACK machine for 1982 | Thu Jan 03 1991 14:36 | 16 |
| Well, over the weekend I accidentally found my copy of Stalick's
"Darned Good Airfoils 3" while looking for something else. It
covers airfoils published by Model Builder in Bob's Free Flight
column from January 1974 thru October 1987. Looking thru the
airfoils, I don't see much that would be of use to RC models. Some
of the Gorringen and Rhode St. Genese airfoils might work. Many of
the rest are VERY strange!
Still, if anyone is interested, I can make copies available (the
material is not copyrighted). If someone else is willing to enter
coordinates of some airfoils, and/or make copies for other noters,
I will send them a copy. Do NOT reply here! Send me mail including
a full US Post Orfice address (office or home - my mailroom
doesn't know most mailstops) and be patient.
Bob Kaplow
|
| 1113.138 | I'm deleting my FOIL library 1/10/91 | POBOX::KAPLOW | Set the WAYBACK machine for 1982 | Thu Jan 03 1991 19:33 | 8 |
| Now that Glenn has included my airfoil text library (many thanks),
I intend on deleting all of the .foil files currently saved on
POBOX::$2$DUA12:[KAPLOW.MISC.AIRFOIL]. I really need the space
back. If anyone sees any reason that I should keep them, or wishes
to provide storage space for them, copy them or send me mail by
January 10th. After that date, consider them deleted.
Bob Kaplow
|
| 1113.139 | airfoil corrections | POBOX::KAPLOW | Set the WAYBACK machine for 1982 | Mon Jan 07 1991 21:55 | 31 |
| Before they go away, I've corrected some errors that I've just
found in the .foil files. Most of them were to to disyxlexic
fingers. A couple were printing errors im my original sources (see
below to see how I corrected these). The corrected FOIL files are
all in hte same directory as before: E180, E201, E211B, HQ1508,
HQ1509, HQ1512, HQ2508, HQ2512 (I must have been really out of it
when I entered the HQ series, only went 3:8 here, but it was very
small print, and several generations of copies...). I'll leave
these at least till Glenn tells me that he has copied them for the
next release of AIRFOIL.
Note that I've found a couple other errors in the coordinates. The
RG12A obviously is trash when plotted. Both the RG15 and the S3014
have extra "/xxxx [ ... ] def" pairs that cause the postscript
interpreter in the printer to barf. Editing them out of the
resulting .PS file works fine.
I did some additional hacking this week, and put together an
airfoil "disassembler". This allows me to take a family of
airfoils, such as the HQ series, and derive the mean line and
thickness distribution that they are all generated from. If Glenn
is real ambitious, I can provide the data to allow automatic
generation of the HQ series, as is now done for the NACA series.
I have similar data that Lister did for the Eppler series. From
what I saw, there is no consistency here, but he generated an
"average" set of lines for some eppler airfoils. As soon as I tie
up some other stiuff, I'll post the distributions for the HQ and
"Eppler" profiles.
Bob
|
| 1113.140 | Possible problem with E387 leading/trailing edge sizes | ZENDIA::REITH | Jim Reith DTN 226-6102 - LTN2-1/F02 | Wed Mar 27 1991 14:12 | 14 |
| I just ran into an interesting problem with the airfoil program. I
wanted to print out the S3014 and E387 foils that have been talked
about recently. I find that when I specify a leading and trailing edge
size for the E387, it reverses them. I did it twice and I got the same
problem. Using the same parameters for the S3014 it cam out right so it
doesn't seem to be a general problem but something with the E387 file
(maybe more, this is just the one I tried)
BTW: in case anyone else is wondering how the two stack up to each
other. There are MAJOR differences. The E387 in 6.75" size (Gnome wing
dimensions ;^) is slightly more than a 1/16" (sheeting thickness I
used) more undercambered and the maximum height above centerline is
visibly farther back. VERY different airfoils. Maybe I'll try an E387
wing next.
|
| 1113.141 | HQ-3.5/10 | LLULL::EDO | Carpe Diem ... | Wed Apr 03 1991 04:17 | 7 |
| Hi all,
I need the ordinates for the profile HQ-3.5/10
I would appreciate very much if some of you can reply this.
Jordi
|
| 1113.142 | derivable from other HQ series airfoils | POBOX::KAPLOW | Set the WAYBACK machine for 1982 | Wed Apr 03 1991 15:30 | 4 |
| With some (much?) work, you can derive it from other HQ airfoild
that have been posted here already. I'm about to leave on vacation
(in 10 minutes no less), or I'd dig up my dissassembled HQ series
and calculate the 3.5-10 for you.
|
| 1113.143 | Looking for E195 Coordinates | USRCV1::BLUMJ | | Wed Jun 19 1991 19:11 | 8 |
| I tried to print out the E195 airfoil using af32.com and it came out
lousy. Does anyone have the coordinates to this airfoil? I think
that they must have been entered in the library with some typos.
Thanks,
Jim
|
| 1113.144 | E214B? B? | SOLVIT::RYDER_A | | Fri Aug 02 1991 01:27 | 3 |
| What is the difference between the E214 and the E214B?
Alton, doing his homework for the Stylus
|
| 1113.145 | different data from different sources | POBOX::KAPLOW | Set the WAYBACK machine for 1982 | Wed Aug 14 1991 20:37 | 7 |
| Beats me! I got two different sets of coordinates from two
different sources. Whenever this happened, I created a `B', `C',
etc. Whenever possible I've included the sources for my data. If
someone has more accurate stuff, or correct versions of the one or
two that are obviously hosed, post them here.
Bob
|
| 1113.146 | Soartech # ? | ELMAGO::TTOMBAUGH | A Fistful of Epoxy | Thu Aug 15 1991 12:39 | 7 |
| The only thing I can think of is that the B version is one of the
E -214 that Selig tested at Princeton.
My Soartech #8 is loaned out so I can't check.
In #8 he labels various airfoils, A, B, C... if there was a variation
in coordinates or construction.
Terry
|
| 1113.147 | Does anyone know if SoarTech #9 has been published yet? | POBOX::KAPLOW | Set the WAYBACK machine for 1982 | Thu Oct 03 1991 20:55 | 0 |
| 1113.148 | No,it hasn't | ELMAGO::TTOMBAUGH | Go ahead...make my plane. | Fri Oct 04 1991 11:52 | 1 |
|
|
| 1113.151 | airfoil library now on ASHISH::RC:...... | ABACUS::RYDER | perpetually the bewildered beginner | Sat Dec 07 1991 09:31 | 7 |
| The airfoil library maintained by Glenn Schrader has moved to
ASHISH::RC:AIRFOIL_V32.*
I haven't used it there yet, but I just did a DIR, and it seems to be OK.
Alton, your not-so-diligent-lately moderator
|
| 1113.154 | airfoils are back | ABACUS::RYDER | perpetually the bewildered beginner | Fri Apr 10 1992 11:03 | 6 |
| The directory and files are back.
ASHISH::RC:AIRFOIL_V32.README
ASHISH::RC:AIRFOIL_V32.TLB
Enjoy.
|
| 1113.155 | Postscript airfoil update? | HANNAH::REITH | Jim HANNAH:: Reith DSG1/2E6 235-8039 | Wed May 27 1992 13:56 | 8 |
| I've been making extensive use of the airfoil program in 1113.125. Has there
been an update to this which includes any new airfoils? I've also gotten
requests for fractional NACA thicknesses which the program can't handle through
the 4 digit input. In going through the .com file, it doesn't appear that the
thickness defined by the last couple of digits is used properly (my plan was to
hardcode it after it was set to allow 7.5%). Any feedback on this?
Anyone have the version dated December 1990. Anyone got anything more recent?
|
| 1113.156 | | CXDOCS::TAVARES | John-Stay low, keep moving | Wed May 27 1992 14:04 | 7 |
| Them's that made it will make no more...the two active developers of
the program have left the company. You can add new airfoils to the
program by following the format of the existing .foil files, and
calling them in when you specify the file type. Of course, please
share the wealth and post them here. Beyond that, the NACA 4-digit
foils are all that are supported for generation. Good program, I use
it a lot.
|
| 1113.157 | AF32.COM | N25480::FRIEDRICHS | Keep'm straight 'n level | Mon Aug 03 1992 12:59 | 15 |
| I can't believe I didn't notice before...
Is anyone else that is using AF32 having a problem where the rib is not
actually being generated to full size?? I didn't notice it until I cut
a 10" chord this weekend, but it was about .75" short!! I went back
and measured the template (including the LE and sheeting) and sure
enough, it was short. So then I measured the templates from the tip
and from the Predator templates... They were about .25" short...
Is anyone else having this problem?? If the chord is getting
shortened, is the airfoil getting flattened too??
Thanks!
jeff
|
| 1113.158 | | CXDOCS::TAVARES | John-Stay low, keep moving | Mon Aug 03 1992 13:45 | 3 |
| I've used it a lot and have not seen this problem. Perhaps the
airfoil coordinates you were using are faulty. I've used it with
Clark-Y and several NACA foils.
|
| 1113.159 | Let us know if you find a more accurate factor | HANNAH::REITH | Jim HANNAH:: Reith DSG1/2E6 235-8039 | Mon Aug 03 1992 13:46 | 14 |
| I looked into it and the code is doing the right thing as far as generating the
postscript is concerned. If the size is off, it's off in all directions. I
looked at the code and find that $setup in the library is where they set the
scale to 72 which is the correct number for converting points to inches. This
would be the value(s) you would want to change to try to get it closer to
actual. The real problem is in the postscript interpreter in the printer since
it isn't printing at 72 points per inch. This is probably an artifact of the
points to DPI conversion in the interpreter since the printer is really printing
300dpi.
I've noticed that certain templates I generated were off. I also have noticed
that boxes and letters I've generated in postscript haven't been the advertised
size. It isn't just this program. It probably varies from printer type to
printer type.
|
| 1113.160 | Use LPS20 not LPS40 | N25480::FRIEDRICHS | Keep'm straight 'n level | Mon Aug 03 1992 14:44 | 9 |
| Well, I just printed the same file out on a LPS-20 that we recently
got and it worked fine!!
So be careful what printer you use and check the sizes! FWIW - It was
an LPS40 that failed me!
cheers,
jeff
|
| 1113.161 | My problems were on an LPS40 also | HANNAH::REITH | Jim HANNAH:: Reith DSG1/2E6 235-8039 | Mon Aug 03 1992 14:52 | 3 |
| And the fix I mentioned to Jeff offline was to take it to the copier and
enlarge it by <size you want> / <size you have>. This would be 111% for a
9" rib => 10" template for example.
|
| 1113.162 | Attention LPS40 users | HANNAH::REITH | Jim HANNAH:: Reith DSG1/2E6 235-8039 | Fri Aug 07 1992 20:10 | 7 |
| The fix I found (a benefit to working in the printserver group) is to print
it using the following command (along with any other switches you use)
Print/param=(data=post,number_up=0)
Number up = zero turns off the printer layup file which might be getting in
the way. Jeff and I have both now been able to print our files true to scale.
|
| 1113.163 | Which airfoil was it? | NEWOA::WINSLADE | | Wed Aug 12 1992 08:23 | 10 |
| Jeff,
Out of interest, which airfoil were you printing (just in
case I want the same one).
I printed a full set of E197 foils for straight taper
between 8.5" and 4.5" on an LPS40 & they came out fine. You gave me a
fright though, 'cos I'd already started cutting them out.
Malcolm
|
| 1113.164 | | N25480::FRIEDRICHS | Keep'm straight 'n level | Wed Aug 12 1992 14:28 | 9 |
| It was an S3014 and S3021... But I believe that Jim has proven that it
is a printer setup issue... Ours happen to be set up and do things
differently, unless I override them...
Jim explains this in one of his notes..
cheers,
jeff
|
| 1113.165 | We've only found it on LPS40s so far | HANNAH::REITH | Jim HANNAH:: Reith DSG1/2E6 235-8039 | Wed Aug 12 1992 14:44 | 5 |
| Yep, reply .162 in this topic gives the parameter changes needed. Seems there
is a way to unknowingly use a layup file but setting number_up=0 turns that
feature off (and doesn't hurt if it wasn't turned on) The file is being
generated properly but the layup file is doing some autoscaling that you want
to disable.
|
| 1113.166 | Computing wing volume (and estimated weight) | RGB::MINER | Dan Miner, DTN:225-4015, HLO2-1/J12 (@ H11) | Mon Aug 31 1992 17:35 | 94 |
| I was trying to do some weight estimates of a composite wing. So
given a foam density of 1.5 pounds per cubic foot (or whatever
density of material you choose), how much should the foam core weigh?
Good question. First, you need to compute the volume the core will
have. Assuming the planform has straight leading and trailing
edges, 2 of the 3 dimensions are easy (span and average chord).
HOWEVER, how do you compute the "average" thickness of the airfoil?
What is required is to compute the area of a given airfoil profile.
Seems difficult, but is it really? After scratchin' the old noggin'
for a few moments, I remembered the high-school calculus method of
trapezoidal integration approximation. (Sounds impressive, but is
really very easy.)
So, I whipped up a C program where the input is the root and tip
airfoil profiles and chords. Its output is the volume of the wing
assuming it is straight tapered and the wing is a foam wing.
[The "foam wing" portion is only true because the program assumes
that the airfoil in the middle is a linear interpolation between the
two templates at the root and tip as a foam wing would be. This
program works equally well for the "typical" balsa rib and spar
construction as long as the root and tip profiles are the same or at
least blend from one to the other the same as a foam wing would.]
The program works under VMS and should also compile and run under
MS-DOS for those of you with home PCs. (Not yet tested w/ MS-DOS.)
NOTE: This program is _not_ unit specific. In other words, it works
just fine with English or metric values.
The program itself is contained in the next reply to this note.
Here is an example output for a wing with:
root: S3021, 10 inch chord
tip: S3014, 7 inch chord
span: 50 inches (for one wing panel = half wing)
------------------------------------------------------------------------------
Root airfoil filename: disk:[directory]S3021.FOIL;1
Tip airfoil filename: disk:[directory]S3014.FOIL;1
Root chord = 10.000000
Tip chord = 7.000000
Single panel Span = 50.000000
%S3021
%S3014
Root airfoil area = 6.21999 square units
Tip airfoil area = 3.06310 square units
Total panel volume = 227.5333 cubic units
Full wing = 2 panels = 455.0665 cubic units
------------------------------------------------------------------------------
Now, since we have the wing volume (455 cu.in.), estimating the
weight is easy. To get the core weight using 1.5 lb./cu.ft. foam,
first convert foam density from (lb./cu.ft.) to (oz./cu.in.):
1.5 lb./cu.ft. * 16 oz./lb. * 1/1728 (cu.ft./cu.in.)
= 0.013889 oz./cu.in.
Now (finally), compute weight of the foam wing core:
455 cu.in. * 0.013889 oz./cu.in. = 6.32 oz. (full wing, 2 panels)
Some (silly?) estimates can also be made. If the same wing were
made out of SOLID balsa (8 lb./cu.ft.) the weight would be roughly
33.7 ounces!! With 1 lb./cu.ft. foam it would be 4.2 ounces.
Note that all of these weight estimates do NOT include the weight of
spars and/or sheeting material (balsa and/or fiberglass and/or
kevlar and/or carbon fiber).
For multiple straight taper planforms (like are popular with the
"high-tech" gliders now), the method still works as long as each
section is a straight taper. Compute each section as if it were a
small wing by itself and add the resulting volumes together.
For complicated planforms (especially elliptical), the airfoil area
must be integrated from root to tip. Anyone that wants help here,
let me know and I'd be glad to compute it for them.
_____
| \
| \ Silent POWER!
_ ___________ _________ | Happy Landings!
| \ | | | | |
|--------|- SANYO + ]-| ASTRO |--| - Dan Miner
|_/ |___________| |_________| |
| / | " The Earth needs more OZONE,
| / not Castor Oil!! "
|_____/
|
| 1113.167 | WING_VOL.C ( Notes> extract/noheader WING_VOL.C ) | RGB::MINER | Dan Miner, DTN:225-4015, HLO2-1/J12 (@ H11) | Mon Aug 31 1992 17:51 | 384 |
| #include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <math.h>
#include <string.h>
/* **************************************************************************
COPYRIGHT (c) 1992 BY Daniel G. Miner
WING_VOL - This program computes the volume of a wing panel using the
trapazoidal numerical integration method.
This program is not unit specific. In other words, the units
are up to the user. If the chords are in inches, then the
volume will be cubic inches. If the chords are centimeters,
then the volume will be cubic centimeters.
Author: Daniel G. Miner
Revision:
1.00 28-Aug-92 DGM
------------------------------------------------------------------------------
To compile the program:
MS-DOS:
(Use your favorite C compiler.)
VMS:
$ cc/nolist/nooptimize wing_vol
$ link wing_vol, sys$library:vaxcrtl/library
------------------------------------------------------------------------------
To use the program:
MS-DOS:
(First, CHDIR to proper directory or include directory in PATH.)
> wing_vol
VMS:
$ wing_vol :== $ disk:[directory]wing_vol
$ wing_vol
where:
disk:[directory] = your disk and directory. Ex: MYDISK:[MYDIR]
The program will then prompt you for:
Root airfoil input file (Coordinate list of airfoil profile)
Tip airfoil input file (Coordinate list of airfoil profile)
Output filename (Use CON: for screen output on MS-DOS,
SYS$OUTPUT for screen output in VMS.)
Root chord length
Tip chord length
Panel span length (Length of one wing panel)
Optionally, you may include some or all of these parameters on the
command line. VMS example:
$ wing_vol S3021.FOIL S7037.FOIL wing1.vol 10.0 7.0 60.0
this computes the volume for a wing with a 10 unit root with S3021
airfoil and a 7 unit S7037 tip airfoil and 60 unit span per panel
(total of 120 unit span).
------------------------------------------------------------------------------
It is assumed that the airfoil input files are in "standard"
coordinate format. That is:
- each point is listed on its own line
- x is listed first, followed by y
- the range of x values is between 0.00 and 1.00 (inclusive)
- the x values decrease along one surface (top/bottom) and
increase along the other surface (bottom/top).
If the input files do not follow this format, inaccurate results
will be computed.
Example portion of an input file:
%S3021
1.00000 0.00000
0.99663 0.00039
0.98679 0.00172
0.97104 0.00419
0.94996 0.00769
[ ... lines deleted here ...]
0.01160 0.01615
0.00374 0.00799
0.00008 0.00099
0.00191 -0.00427
0.00984 -0.00852
0.02320 -0.01232
0.04178 -0.01547
[ ... lines deleted here ...]
0.94876 -0.00107
0.97048 -0.00035
0.98660 0.00003
0.99661 0.00006
1.00001 -0.00000
**************************************************************************
*/
/* INTEGRATION_STEPS defines how many steps the wingspan will be broken */
/* up to perform the integration. For example, if the wingspan were */
/* 60 and INTEGRATION_STEPS were 120, then the program would integrate */
/* every 0.5 units. */
/* Increasing this number increases the accuracy, but also increases */
/* the computational time. */
/* Note that if the root and tip airfoil areas are identical, then the */
/* program uses only one step (and averages the areas). */
#define INTEGRATION_STEPS 1000
#define MAX_LINE 256 /* Number of characters per line */
#define err_exit(str) { fprintf(stderr, "%s\n", str); exit(EXIT_FAILURE); }
#ifndef VAXC
#define TRUE 1
#define FALSE 0
#endif
FILE *root_fp, *tip_fp, *out_fp;
#define FILENAME_MAX 256
char root_file[FILENAME_MAX];
char tip_file[FILENAME_MAX];
char out_file[FILENAME_MAX];
int batch_mode = FALSE;
/* Function declarations */
double get_area (FILE *airfoil_fp);
double get_double_arg (int argc, char*argv[], int arg_num, char *prompt_msg);
double integrate (double area1, double ch1, double area2, double ch2,
double len, int steps);
FILE *file_arg (int argc, char *argv[], int arg_num, char *filename,
char *access, char *prompt_msg);
FILE *open_file (char *filename, char *access, char *prompt_msg);
FILE *get_file (char *filename, char *access, char *prompt_msg);
int process_options (char *cp);
int process_options_funct (char *cp, int flag);
main (argc, argv)
int argc;
char *argv[];
{
int i, steps;
double root_ch, tip_ch, span, root_area, tip_area, volume, ra, ta;
printf (" WING_VOL - Computes the volume of a wing\n");
printf (" Version 1.00 28-Aug-92 Daniel Miner\n\n");
process_options (argv[0]); /* Process any options that might appear
after command */
root_fp = file_arg (argc, argv, 1, root_file, "r", "root airfoil data");
tip_fp = file_arg (argc, argv, 2, tip_file, "r", "tip airfoil data");
out_fp = file_arg (argc, argv, 3, out_file, "w", "output");
for (i = 4; i < argc; i++) /* Get options after last filename */
if ( ! process_options(argv[i]) && i > 6)
{ fprintf (stderr, "****** Extra parameter. \"/\" option expected.");
fprintf (stderr, "\n\"%s\" - Ignored.\n",argv[i]);
}
root_ch = get_double_arg (argc, argv, 4, "root chord");
tip_ch = get_double_arg (argc, argv, 5, "tip chord");
span = get_double_arg (argc,argv, 6, "span for one panel (1/2 total span)");
printf ("\n");
fprintf (out_fp, "Root airfoil filename: %s\n", root_file);
fprintf (out_fp, "Tip airfoil filename: %s\n", tip_file);
fprintf (out_fp, "Root chord = %f\n", root_ch);
fprintf (out_fp, "Tip chord = %f\n", tip_ch);
fprintf (out_fp, "Single panel Span = %f\n\n", span);
root_area = get_area (root_fp);
tip_area = get_area (tip_fp);
ra = root_area * root_ch * root_ch;
ta = tip_area * tip_ch * tip_ch;
fprintf (out_fp, "\nRoot airfoil area = %8.5f square units\n", ra);
fprintf (out_fp, "Tip airfoil area = %8.5f square units\n", ta);
steps = INTEGRATION_STEPS;
if (root_area == tip_area && root_ch == tip_ch)
steps = 1;
volume = integrate (root_area, root_ch, tip_area, tip_ch, span, steps);
fprintf (out_fp, "\nTotal panel volume = %8.4f cubic units\n", volume);
fprintf (out_fp, "\tFull wing = 2 panels = %8.4f cubic units\n", 2*volume);
/* volume = 0.5 * (ra + ta) * span; */
/* fprintf (out_fp, "average method = %8.4f cubic units\n", volume); */
fclose (out_fp);
}
/* ------------------------------------------------------------------------- */
double get_area (FILE *airfoil_fp)
{
int first = TRUE;
char line[MAX_LINE]; /* Input line buffer */
char *linept = line; /* Pointer into line */
double x, y, lastx, lasty, area = 0.0;
while (fgets (line, MAX_LINE, airfoil_fp) != NULL)
{ if (sscanf (line, "%le %le", &x, &y) != 2)
fprintf (out_fp, "%s", line); /* Echo comments to output */
else
{ if (first)
first = FALSE;
else
{ if (x < lastx)
area += 0.5 * (y + lasty) * fabs (x - lastx);
else
area -= 0.5 * (y + lasty) * fabs (x - lastx);
}
lastx = x;
lasty = y;
}
#ifdef DEBUG
fprintf (out_fp, "Area: %f x/y: %s", area, line);
#endif
}
close (airfoil_fp);
return ( fabs (area));
}
/* ------------------------------------------------------------------------- */
double get_double_arg (int argc, char *argv[], int arg_num, char *prompt_msg)
{ double d;
if (argc > arg_num && sscanf (argv[arg_num], "%le", &d) == 1)
return (d);
do
{ printf ("\nEnter %s : ", prompt_msg);
} while (scanf ("%le", &d) != 1);
return (d);
}
/* ------------------------------------------------------------------------- */
double integrate (double area1, double ch1, double area2, double ch2,
double len, int steps)
{ double lasta, a, ch, p, dx, vol = 0.0;
int i;
lasta = area1 * ch1 * ch1;
dx = len / (double) steps;
/* printf ("\n\ndx = %f\n\np\ta\tvol\n\n", dx); */
for (i = 1; i <= steps; i++)
{ p = (double) i / (double) steps;
ch = (ch1 * (1.0-p)) + (ch2 * p);
a = (area1 * ch * ch * (1.0-p)) + (area2 * ch * ch * p);
vol += 0.5 * (a + lasta) * dx;
/* printf ("%f %f %f\n", p, a, vol); */
lasta = a;
}
return (vol);
}
/* ------------------------------------------------------------------------- */
FILE *file_arg (int argc, char *argv[],
int arg_num, /* Which argument to use */
char *filename, /* The actual filename that was opened */
char *access, /* Type of access requested ("r" or "w") */
char *prompt_msg) /* Message for prompt (if no arg.) */
{
FILE *file_pt;
if (argc > arg_num)
{ strncpy (filename, argv[arg_num], FILENAME_MAX);
file_pt = open_file (filename, access, prompt_msg);
}
else
file_pt = get_file (filename, access, prompt_msg);
if (fgetname (file_pt, filename) == 0)
err_exit ("\n\t****** Program error - Funct: file_arg.\n");
return (file_pt);
}
/* ------------------------------------------------------------------------- */
/* Returns filename and file pointer */
FILE *open_file (char *filename, char *access, char *prompt_msg)
{
FILE *file_pt;
process_options (filename); /* Remove options from filename */
if ((file_pt = fopen (filename, access)) == NULL)
{ fprintf (stderr,"\n\t****** Error - Unable to open ");
fprintf (stderr, "%s file:\n '%s'\n", prompt_msg, filename);
file_pt = get_file (filename, access, prompt_msg);
}
return (file_pt);
}
/* ------------------------------------------------------------------------- */
/* Returns filename and file pointer */
FILE *get_file (char *filename, char *access, char *prompt_msg)
{
FILE *file_pt;
if (batch_mode)
{ fprintf (stderr, "\n****** Error opening %s file: %s\n\n",
prompt_msg, filename);
exit (EXIT_FAILURE);
}
printf ("Enter %s filename: ", prompt_msg); /* Prompt user for filename */
scanf ("%s", filename);
printf ("\n");
file_pt = open_file (filename, access, prompt_msg); /* Try to open it */
return (file_pt);
}
/* ------------------------------------------------------------------------- */
int process_options (char *cp)
{ int valid_parameter;
valid_parameter = FALSE;
while ((cp = strchr (cp, '/')) != NULL)
{ *cp++ = '\0'; /* Terminate string at '/' character */
if (_toupper (cp[0]) == 'N' && _toupper (cp[1]) == 'O')
{ cp += 2; /* Process "/NO___" option */
valid_parameter |= process_options_funct (cp, FALSE);
}
else
valid_parameter |= process_options_funct (cp, TRUE);
}
return (valid_parameter);
}
/* ------------------------------------------------------------------------- */
int process_options_funct (char *cp, int flag)
{
char *cp2;
switch ( _toupper(*cp))
{ case 'B': batch_mode = flag; /* Set BATCH mode flag */
break;
default: /* Ignore bad values */
if ((cp2 = strchr (cp, '/')) != NULL)
*cp2 = '\0'; /* Temporarily terminate at '/' char */
fprintf (stderr,
"\n****** Bad option \"/%s\" - ignored.\n", cp);
if (cp2 != 0)
*cp2 = '/'; /* Restore '/' if necessary */
return (FALSE);
}
return (TRUE); /* Good parameter */
}
/* ------------------------------------------------------------------------- */
|
| 1113.168 | David B. Fraser | RGB::MINER | Dan Miner, DTN:225-4015, HLO2-1/J12 (@ H11) | Wed Sep 16 1992 14:52 | 19 |
| According to the newest issue of Model Builder, one of the pioneers
of modern airfoil research has passed away. The very short article
states that David B. Fraser was killed in a small plane crash while
attempting an emergency landing.
Mr. Fraser was one of the 3 authors for Soartech #8 that lists the
data compiled from the wind tunnel experiments at Princeton.
(Michael Selig and John Donovan are the other 2 authors.)
_____
| \
| \ Silent POWER!
_ ___________ _________ | Happy Landings!
| \ | | | | |
|--------|- SANYO + ]-| ASTRO |--| - Dan Miner
|_/ |___________| |_________| |
| / | " The Earth needs more OZONE,
| / not Castor Oil!! "
|_____/
|
| 1113.169 | Airfoil wanted | HANNAH::REITH | Jim HANNAH:: Reith DSG1/2E6 235-8039 | Wed Sep 16 1992 15:16 | 3 |
| I've gotten a request for some Quickee 500 wings. They are using the NACA
airfoil 6420. The current code doesn't actually generate NACA airfoils. Does
anyone have the datapoints for this airfoil?
|
| 1113.170 | Sure it does! | CXDOCS::TAVARES | John-Stay low, keep moving | Thu Sep 17 1992 13:52 | 7 |
| Jim, have I missed something? The last version of the airfoil program
put up by (whatshisname? I always get it wrong) did have the
capability to generate an NACA foil. I've used it to create a fairly
nice semi-symetrical foil and it does look like the illustration I
used. Haven't compared the numbers yet though. Anyway give it a try,
and if another version has been put up in the meantime, I have the
"good" one.
|
| 1113.171 | I thought I had the latest but... | HANNAH::REITH | Jim HANNAH:: Reith DSG1/2E6 235-8039 | Thu Sep 17 1992 14:02 | 3 |
| Which version are you using? I've got a version of AF32.com and it tells
me that it can't find it in the library. instead of generating it. Maybe I'm
specifying the inputs wrond? Could you mail me a copy of your .com and .tlb?
|
| 1113.172 | It works fine w/ NACA-6420 | RGB::MINER | Dan Miner, DTN:225-4015, HLO2-1/J12 (@ H11) | Thu Sep 17 1992 17:27 | 11 |
| From the AIRFOIL_V32.README file...
3. NACA four digit airfoils are specified by entering
NACA-mctt<return>. "m" is the point of maximum camber specified in
tenths of the chord from the leading edge. "c" is the amount of
camber specified in tenths of the chord. "tt" is the thickness of
the airfoil in percent. For instance, entering NACA-4212 specifies
an airfoil that is 12% thick which has a camber of 20% of the chord
with the point of maximum camber occuring at the 40% chord point.
(Make sure you type "NACA-6420" and not lowercase: "naca-6420")
|
| 1113.173 | You don't want the NACA-6420... | RGB::MINER | Dan Miner, DTN:225-4015, HLO2-1/J12 (@ H11) | Thu Sep 17 1992 17:35 | 3 |
| Jim, are you sure it's the 6420??!?!?! That's 20% thickness!!!
It sure doesn't look like a fast airfoil... Maybe 6410 or 6408...
but 6420?????? I can't believe it...
|
| 1113.174 | UBD = User Brain Damage | HANNAH::REITH | Jim HANNAH:: Reith DSG1/2E6 235-8039 | Thu Sep 17 1992 18:02 | 4 |
| I'll be reverifying the airfoil but I'm pretty sure he said 6420. I'll agree
that 20% seems a bit much for something that's supposed to go fast.
I'll bet I didn't type it in uppercase.
|
| 1113.176 | NACA digit representations? | RGB::MINER | Dan Miner, DTN:225-4015, HLO2-1/J12 (@ H11) | Thu Sep 17 1992 18:31 | 5 |
| Can someone find out what the first 2 digits on the NACA foils are?
The digits represent chamber and location of max. chamber, but which
one is which?
(The .COM and .README say opposite things...)
|
| 1113.177 | | CXDOCS::TAVARES | John-Stay low, keep moving | Fri Sep 18 1992 14:43 | 12 |
| From my NACA foils article: the first number is the maximum amount of
camber in percent of chord. The second is the location of the maximum
point in tenths of chord back from the leading edge. The last two
numbers are percent thickness.
The article is from Model Aviation, November 1984, Plotting the
Four-Digit, Five-Digit, and 6-Series NACA AIRFOILS. I sent a few
copies out last time (as referenced in an earlier note of this
string), and will send copies to anybody who mails me their address.
I've checked the program and to my knowledge it does not reverse the
two numbers.
|
| 1113.178 | AIRFOIL_V32.COM correct; .README file wrong | RGB::MINER | Dan Miner, DTN:225-4015, HLO2-1/J12 (@ H11) | Fri Sep 18 1992 18:08 | 8 |
| Based on the info. in .177, I have deleted note .175 which was in
error. The program does indeed seem to do the correct thing for
generating NACA airfoils.
Just be aware that the .README documation is wrong and lists the
first 2 digits backwards from the correct way.
- Dan
|
| 1113.179 | I vote for Dan Miner - keeper of airfoil | KAY::FISHER | The higher, the fewer | Mon Sep 21 1992 17:54 | 19 |
| ><<< Note 1113.178 by RGB::MINER "Dan Miner, DTN:225-4015, HLO2-1/J12 (@ H11)" >>>
> -< AIRFOIL_V32.COM correct; .README file wrong >-
Dan - since the original author is gone - and since you know PostScript
better and anyone else I know - why don't you update the files
and point us all to the newest latest release area.
In old DEC terms - if you can identify a problem you own it.
As soon as you have done this then we can start sending you
requests for enhancements.
1. Please change any code that makes it case sensitive to user inputs.
Bye --+--
Kay R. Fisher |
---------------O---------------
################################################################################
|
| 1113.180 | 6420 you said, for speed ??? | KBOMFG::KNOERLE | | Tue Sep 22 1992 06:39 | 9 |
|
I was quite surprized : The NACA calculation did work ! For the first
time. I tried it often without success. You just ought to do it right.
BTW, the NACA 6420 (?) cannot possibly be an airfoil for
hot_air_balloons ? For sure not for speed models !
Bernd
|
| 1113.181 | Yeah, but we thin it down... | HANNAH::REITH | Jim HANNAH:: Reith DSG1/2E6 235-8039 | Tue Sep 22 1992 12:45 | 6 |
| Well, I met one of the racers last night and in our conversations we talked
about the Quickee 500 wing cores. He reaffirmed the 6420 airfoil that they
use but then he says that they thin it down to 1 3/16" thick (10" chord).
I've discovered that you can't talk airfoils with many of these guys 8^)
They seem to be flying something closer to a 6412 in reality.
|
| 1113.182 | still not convinced | KBOMFG::KNOERLE | | Tue Sep 22 1992 14:09 | 10 |
|
Jim,
I printed both airfoils, a NACA-6412 and a 12% reduced NACA-6420. I'm
still not convinced that they use a undercambered (?) airfoil for Pylon
racing. Both airfoils look more like a glider airfoil. I thought a
semi-symetrical would be closer to what they use. I'm still
interested...
Bernd
|
| 1113.183 | Haven't seen one first hand... | HANNAH::REITH | Jim HANNAH:: Reith DSG1/2E6 235-8039 | Tue Sep 22 1992 14:36 | 8 |
| Can't argue with you. I haven't actually seen any of the planes. I'm just
trying to cut what the customer requests. There are minimum thickness
requirements in the Quickee 500 rules and those are the ones that they're
designing to. I'll be getting a sample set of cores to compare to when
they put in their order. I'll let you know what I find.
BTW: they are using Lee modified K&B engines which go for about $100 in
the NEPRO events. They're doing everything they can to keep costs down.
|
| 1113.184 | Can root and Tip sections Differ? | SHIPS::HORNBY_T | | Mon Jan 18 1993 10:49 | 8 |
| Has anyone taken ownership of the Airfoils Software. (Airfoils_v32)
Does anyone know how to (or sugest any posible work-around) get a root and
tip foil which are different out of this s/w. eg SD7032 root and
SD3014 tip. (I know how to vary the thickness of the same section).
Thanks Trev.
|
| 1113.185 | A solution if you aren't doing an elliptical wing | 3D::REITH | Jim 3D::Reith MLO1-2/c37 223-2021 | Mon Jan 18 1993 11:15 | 6 |
| I've played with it some (to get non-integer NACA sections). It doesn't really
interpolate between the root and tip so different sections wouldn't work. I
assume you want to generate rib patterns since all you need do is run it twice
with single sections to generate foam templates. You can do the same thing
with balsa by stacking the ribs between the root and tip templates and then
sanding the stack into shape. I hate doing this but others swear by it.
|
| 1113.186 | | CXDOCS::TAVARES | John-Stay low, keep moving | Mon Jan 18 1993 13:14 | 2 |
| I haven't done this, but there is a percentage factor in there that
you can diddle.
|
| 1113.187 | | NEWOA::WINSLADE | | Tue Jan 19 1993 12:14 | 7 |
| Hi Trev, how's Solent?
Do it Jim's way in .185, much more character building..
Malcolm
|
| 1113.188 | modifying airfoil_v32 | FRUST::HERMANN | | Fri Jan 22 1993 08:49 | 54 |
| hi fans,
re .184,
i am actually working on the airfoil-program. new features i will be adding:
1) marks for bow-cutting
2) an improved-placing-the-foil-on-the-paper-algorithm
this is necessary for the following reasons:
3) independency of papersize
and
4) ability to specify chord etc in inches or millimeters
5) "negative" ribs, i.e. ribs in a bounding box
6) placing the ribs in the bounding box with AoA, distance from box-edges etc
7) replaced (and exact!) skin algorithm
8) your ideas go here...
status:
1) almost done, last polishing missing
2), 3), 4) and 7) started
5) and 6) still thinking about some special ideas i have with the boxing in.
i also need to talk to an aerodynamics guy before i start with 5) and 6)
i plan to be ready on end of march.
5) and 6) would ease even further the creation of what we in germany call
a "strak". a strak is basically two different foils at root and tip.
what i need from you guys, is the following:
- answers to 8)...
example: what about a routine, that would extract our foils into DXF-format?
this would enable us to import them into cad-programs. i really do not see
the need for this option, because the program would do everything we want,
but only PRINTING it. playing around on the screen is not possible, but
would be on a cad program.
- please send me all your favorite foils you have hacked up until know, to
increase the library.
mail them via vms-mail: frust::hermann or a-in-1: joerg hermann @frs
joe t.
|
| 1113.189 | | GAUSS::REITH | Jim 3D::Reith MLO1-2/c37 223-2021 | Fri Jan 22 1993 12:08 | 4 |
| The different airfoils at root and tip part needs to compensate for the
fact that the .foil coordinates aren't required to be uniformly distributed.
I'd like to see a centerline printed so you can do incidence alignment.
|
| 1113.190 | Thanks and more requests | SHIPS::HORNBY_T | | Fri Jan 22 1993 12:42 | 16 |
| Joe,..
Thanks for your OWNERSHIP I look forward to the results.
I run the CAD office in Solent so the CAD output would be very nice.
Re New requests.. (I think Kay mention it before)
Define Spars Width,Height,position: Root and Tip.
Thanks Trev.
PS. Anyone posted RG14 anywhere, otherwise I'll do it.
|
| 1113.191 | Waytago! | CXDOCS::TAVARES | John-Stay low, keep moving | Fri Jan 22 1993 13:18 | 1 |
| I hereby bestow upon you the coveted rank of Conference Hero.
|
| 1113.192 | sounds good | MISFIT::BLUM | | Fri Jan 22 1993 13:52 | 15 |
| Joe,
Thanks for taking on this chore. I would like to see the
center camber line mentioned by Jim Reith, and equally spaced,
numbered vertical lines to assist with hot wire core cutting.
I am sending you the coordinates for Andrew Hollom's 7% F3B
airfoil-AH21/ and. Nic Wright's 7% F3B airfoil RG14A-1.4/7.0.
These foils are optimized for the F3B distance task and should
be FAST******************************!!!!!
Thanks again,
Jim
|
| 1113.193 | I'm not sure we're asking for the same thing | GAUSS::REITH | Jim 3D::Reith MLO1-2/c37 223-2021 | Fri Jan 22 1993 14:18 | 5 |
| I'm not looking for a mean camber line. I'm looking for a straight line
extending beyond the airfoil which passes through the two outermost points.
I ran into problems when I changed airfoils on a plane last year. My
incidence was wrong. An incidence meter works on a plane but the centerline
works when drawing plans.
|
| 1113.194 | Friday humor!. | CSTEAM::HENDERSON | Competition is Fun: Dtn 297-6180, MRO4 | Fri Jan 22 1993 14:23 | 1 |
| Incidence meter - How many times you have an indci"DENT". :-)
|
| 1113.195 | More on spars | NEWOA::WINSLADE | | Mon Jan 25 1993 07:25 | 6 |
| Further to .1, would the spar details allow for the specified sheeting
(if any), and...how about tapered spars (please).
With undying gratitude,
Malcolm
|
| 1113.196 | Spars and tapers | SHIPS::HORNBY_T | | Tue Jan 26 1993 14:56 | 5 |
| Malcom,
By defining the spar at root and Tip I was hoping this would create
a taper if required.
Trev
|
| 1113.197 | Camber questions | MISFIT::BLUM | | Mon Feb 22 1993 14:23 | 17 |
| Has anyone seen a polar of the SD6060 or E374 airfoils? I am
curious how the L/D compares with the F3B airfoils. I understand
why a symmetrical airfoil would be desireable for inverted flight,
rolls, etc. but not on a thermal soarer. Some of the older cross
country ships used the E374, which is why I am curious.
Also can anyone explain the term "camber" as it applies to airfoils.
How is the % camber of an airfoil derived. How does camber relate
to symmetrical, flat bottom, and undercambered airfoils?
Thanks,
Jim
|
| 1113.198 | Here's an off the cuff answer until I can check my books... | 3D::REITH | Jim 3D::Reith MLO1-2/c37 223-2021 | Mon Feb 22 1993 14:30 | 6 |
| Mean Camber is the line that is equidistant from the top and bottom surface.
The percentage camber for an airfoil is the amount this deviates from a
horizontal line. I'm not sure what the percentage indicates but is has something
to do with the maximum deviation measurement. I can look it up in my sources at
home. Aerodynamics was one of the things that lead me into Physics in college.
I had designed and built a wind tunnel... 8^)
|
| 1113.199 | Modifications to airfoil_v32 progressing | FRUST::HERMANN | | Fri Mar 19 1993 06:11 | 23 |
| hi fans,
re .188: before i am off for a long work-holiday-training trip, i wanted to
give you a status on the airfoil program:
- yesterday evening i finally succeeded with the placing the foil on the paper
problem. the rest should be easier.
- bow-marks are available in any number.
- a centerline is printed. does anybody want the centerline to extend
beyond the foil?
i apologize for being delayed, but having finally real work again is not
one of the badest things in these days.
- please send me all your favorite foils you have hacked up until know, to
increase the library.
mail them via vms-mail: frust::hermann or a-in-1: joerg hermann @frs
joe t.
|
| 1113.200 | yeah | KBOMFG::KNOERLE | | Fri Mar 19 1993 08:56 | 9 |
|
Hallo Joerg,
I'm anciously awaiting your new version. So where are your field test
units ?
Bernd
|
| 1113.201 | mods to Airfoil program | KAY::FISHER | The higher, the fewer | Fri Mar 19 1993 16:21 | 13 |
| 1113.202 | | N25480::FRIEDRICHS | APACHE::FRIEDRICHS | Fri Sep 17 1993 16:39 | 9 |
| OK, what do people do when the airfoil is larger than 11" chord??
I have a LPS20 that has larger paper, but the airfoils are still
printed in an 8.5x11 space (and parts are lost...) Or do people
just paste the pieces together??
Thanks!
jeff
|
| 1113.203 | | GAUSS::REITH | Jim 3D::Reith MLO1-2/c37 223-2021 | Fri Sep 17 1993 16:58 | 1 |
| Yep, I just print out two copies and paste the halves together
|
| 1113.204 | | CXDOCS::TAVARES | Have Pen, Will Travel | Fri Sep 17 1993 21:35 | 2 |
| You should modify your print command to specify the tray that has the
larger paper. I've printed airfoils to 12 inches that way.
|
| 1113.205 | | APACHE::FRIEDRICHS | APACHE::FRIEDRICHS | Sat Sep 18 1993 11:52 | 5 |
| I have used the middle tray, but they still get chopped off... Do you
also need to change to landscape or to portrait??
jeff
|
| 1113.206 | Landscape! | CXDOCS::TAVARES | Have Pen, Will Travel | Mon Sep 20 1993 02:51 | 1 |
| I've printed them in landscape.
|
| 1113.207 | AF40 will check the paper size | FRUST::HERMANN | | Mon Sep 20 1993 14:43 | 6 |
| HI ALL,
THE NEW VERSION OF AIRFOIL WILL CHECK THE PAPERSIZE. SO YOU CAN PRINT
LARGER FOILS ON LARGER PAPERS.
JOE T. (who's sad, 'cause his motorcycle engine broke today)
|
| 1113.208 | | GAUSS::REITH | Jim 3D::Reith MLO1-2/c37 223-2021 | Mon Sep 20 1993 17:24 | 1 |
| I believe the older af32.com assumed a 10.5" max length
|
| 1113.209 | Where is it?? | N25480::FRIEDRICHS | APACHE::FRIEDRICHS | Mon Sep 20 1993 17:31 | 9 |
| Joe,
I looked through the old notes... Where can I get a copy of AF40
from??
Thanks very much!
jeff
|
| 1113.210 | | GAUSS::REITH | Jim 3D::Reith MLO1-2/c37 223-2021 | Mon Sep 20 1993 17:45 | 7 |
| Yeah Joe, when are you going to let the cat out of the bag and announce it?
Making it available is probably the best QA you could get 8^)
Has anyone else noticed that the SD8020 .foil file in the af32 library has a
glitch in it? It's supposed to be symetrical but there's a bump on the bottom
(so I just paste together two mirrored tops)
|
| 1113.211 | hold the line.... | FRUST::HERMANN | | Tue Sep 21 1993 06:46 | 14 |
| hi folx,
yes, af40 is still not available.
i have reached a quite steady state, although more ideas are coming up. (how
about a dihedral option?)
but i promise i will announce it as soon as i've got the user guide ready.
it has so many options it really needs one.
in two weeks the daylight saving is turned off here in germany, this might
speed up work on it again.
cheers
joe t.
|
| 1113.212 | Printing on A3 | SHIPS::HORNBY_T | Soarers are rarely Silent | Wed Sep 22 1993 21:52 | 13 |
| back to the question of 11" chords (anyway bigger than A4).
If you type (at the dollar prompt) "Help print_param" you should find all
your answers.
I think it goes something like
$ Print/que=Your_que_name/param=(page_s=a3,page_orient=landscape,data_type-
=postscript)
you can print foils up to 15"
Regards Trevor
|
| 1113.213 | 11 inch cord? | KAY::FISHER | The higher, the fewer | Thu Sep 23 1993 16:03 | 17 |
| > <<< Note 1113.202 by N25480::FRIEDRICHS "APACHE::FRIEDRICHS" >>>
>
> OK, what do people do when the airfoil is larger than 11" chord??
R we talking about a .60 size 1-decker here?
If so remember I didn't say no - I said "ask me again later".
I don't have any spare 40 size engines - but I've got a few 60s
around!
If this is your new club design - please start a note about it.
Bye --+--
Kay R. Fisher |
---------------O---------------
################################################################################
|
| 1113.214 | You're the one that wanted to get me there next year 8^) | GAUSS::REITH | Jim 3D::Reith MLO1-2/c37 223-2021 | Thu Sep 23 1993 16:28 | 5 |
| If you output directly to the foam cutter, you don't run into any of
these problems 8^)
I have a couple of .60s as well that I wouldn't mind bashing into
balloon sticks next year. Tell us more...
|
| 1113.215 | | N25480::FRIEDRICHS | APACHE::FRIEDRICHS | Thu Sep 23 1993 17:35 | 14 |
| Well, actually, the wing I am currently cutting is for my Junkers D-8
that I bought down there.. It will have a 120 on it...
However, Mike and Joe are talking about scaling up the current
.40 eindecker to .60 size..
Oh yea, my Junkers will just happen to have the SD6060 airfoil that
we have used on the Eindecker...
OK, I will keep you both informed.. Anyone else (sorry Lamar, you
didn't finish the *last* one!!)
jeff
|
| 1113.216 | | GAUSS::REITH | Jim 3D::Reith MLO1-2/c37 223-2021 | Thu Sep 23 1993 17:49 | 4 |
| Well, if you end up doing another club kit build, I'd be willing to
do the cores to get into the loop.
Lamar's in TAY and I still heard the ricochet in the Mill!
|
| 1113.217 | So! :-) | MICROW::PHILLIPS | "DECtp Engineering TAY1-2 DTN 227-4314" | Thu Sep 23 1993 17:49 | 6 |
| Re: Jeff,
So I know of a certain Proctor Nieuport(sp?) that someone hasn't
finished yet! :-) :-)
-Lamar
|
| 1113.218 | | N25480::FRIEDRICHS | APACHE::FRIEDRICHS | Thu Sep 23 1993 18:54 | 1 |
| Yea, well, uh..... What's your point???!!
|
| 1113.219 | SD8020 in the library is wrong | GAUSS::REITH | Jim 3D::Reith MLO1-2/c37 223-2021 | Thu Nov 04 1993 18:23 | 17 |
| Back to basics:
We seem to have mistyped a digit in the .foil file for the SD8020
symetrical airfoil. This is what's causing the notch that you see.
Since it's symetrical, the upper and lower surfaces should be
within 1 of each other but upon examination we find:
%Upper Surface
0.62777 0.03535
%Lower Surface
0.60777 -0.03534
From my investigations and examination of the .foil file in
the library, I believe the correct lower value is:
%Lower Surface
0.62777 -0.03534
|
| 1113.220 | Translate please | SHIPS::HORNBY_T | Soarers are rarely Silent | Thu Nov 18 1993 12:02 | 16 |
| I have some CO-ORDinates for the Selig 5020-084 but I'm have a litte
trouble converting the format. Any ideas...
Sample part of the table
%CHORD. 0 2E-3 0.219 0.308 0.833 1.226 ..ETC >> 100
----------------------------------------------------------------------
%TOP/B 0 -4.9E-2 0.613 -0.507 1.401 -0.815 ..ETC >> 0
My guess is the TOP/B is alternating surfaces but what is the 'E-2' ??
Regards Trevor
|
| 1113.221 | algebra.... | KBOMFG::KNOERLE | | Thu Nov 18 1993 12:18 | 16 |
|
>>> %CHORD. 0 2E-3 0.219 0.308 0.833 1.226 ..ETC >> 100
>>> ----------------------------------------------------------------------
>>> %TOP/B 0 -4.9E-2 0.613 -0.507 1.401 -0.815 ..ETC >> 0
The -4.9E-2 is the exponential way to say -0.049. (-4.9 x 10^-2)
Your assumption is right, top and bottom is alternating. Not quite
common though.
Bernd
|
| 1113.222 | Add It To The Library | CXDOCS::TAVARES | Have Pen, Will Travel | Thu Nov 18 1993 13:20 | 3 |
| Check our airfoil library in past notes; this one may be in there.
Else, why not input it for all of us--lot easier than plotting the
points!
|
| 1113.223 | CJ-5WD Flying Wing Coords | SHIPS::HORNBY_T | Soarers are rarely Silent | Fri Nov 19 1993 07:32 | 38 |
| CJ-5WD - co-ordinates used on the Flying Wing TIME BANDIT
1.00000 0.001000
0.95000 0.002440
0.90000 0.005060
0.80000 0.014020
0.70000 0.026700
0.60000 0.039830
0.50000 0.052590
0.40000 0.062500
0.30000 0.068450
0.25000 0.068080
0.20000 0.066510
0.15000 0.062580
0.10000 0.053690
0.07500 0.046760
0.05000 0.037830
0.02500 0.026890
0.01250 0.018930
0.00000 0.000000
0.01250 -0.014030
0.02500 -0.019070
0.05000 -0.025110
0.07500 -0.027960
0.10000 -0.029230
0.15000 -0.028320
0.20000 -0.026390
0.25000 -0.024420
0.30000 -0.022450
0.40000 -0.020420
0.50000 -0.018330
0.60000 -0.018210
0.70000 -0.020040
0.80000 -0.017940
0.90000 -0.011920
0.95000 -0.007040
1.00000 -0.001000
|
| 1113.224 | Help Please - Big foils | SHIPS::HORNBY_T | Soarers are rarely Silent | Tue Nov 23 1993 13:00 | 18 |
|
I was rather cocky when I answered the the problem about printing to A3
sized output (wing foils bigger than 10.5") back in 1113.212, I am now
eating humble pie cos I can't print out my 14" chords.
I can print on A3 paper but the offset somewhere in the poscscript file
pushes everything after about 10" off the page.
Help does anyone have a solution. Perhaps I could edit the postscipt
file? (I am familiar with some postscript formats but not this one)
HELP
Thanks Trev.
PS:
Joe are you still there? any news with the next release of AF.COM ??
|
| 1113.225 | Try these | QUIVER::WALTER | | Tue Nov 23 1993 16:30 | 15 |
| One of the few Postscript tricks I know is "x y translate", where x
and y are in points (a point is 1/72"). So, to offset 10" side to side,
you would enter into the postscript file, near the top:
720 0 translate
You will have to experiment to get the right direction (negative or
positive).
If I remember correctly, there is also a "x y scale" command and
"r rotate", where x and y are scale mulitpliers, and I think r is in
degrees.
Dave
|
| 1113.226 | Producing LARGE foils | SHIPS::HORNBY_T | Soarers are rarely Silent | Wed Nov 24 1993 13:00 | 28 |
| Dave,
Thanks. About the same time I discovered this (by merging a
different style of postcript file)..
FOR PRINTING LARGER FOILS REQUIRING A3 paper. (10.5"-15.5")
o process the foil you require as normal using the AFxx.COM
o edit the ".PS" file which is generated by adding the following line
straight after the comments section at the top of the file. i.e.
after the lines stop beginning with "%"
[1.0 0.0 0.0 1.0 0.0 360] contact
this will shift the image on the paper by 5"
o print the new edited file on your postscript printer which has A3
capability e.g.
$ Print/que=QUENAME/param=(page_s=A3,page_o=landscape) FILENAME.ps
Regards Trev
|
| 1113.227 | af - work in progress | FRUST::HERMANN | | Mon Nov 29 1993 13:55 | 13 |
| hi folx,
yes, i am still alive, recovering from a very strong cold.
yes, i am still in the company.
yes, i am still working on the af40 version. i have to admit that 2 monthes
passed without anything being done on af, but i hope that around christmas
i will have the time to bring it into a state that can be released.
as i am switching projects right now, some uncertainity creeps up though...
sorry, i have no better information at the moment.
cheers
joe t.
|
| 1113.228 | E387 coordinates | DRAC::EDO | Carpe Diem ... | Tue Nov 30 1993 09:48 | 73 |
| Hi all,
Attached are a coordinates for Eppler 387 airfoil. It has 62 coordinates
and draw a more accurate airfoil than the original coordinates in AF32.COM
library.
Jordi
1.00000 0.00000
0.99677 0.00043
0.98729 0.00180
0.97198 0.00423
0.95128 0.00763
0.92554 0.01184
0.89510 0.01679
0.86035 0.02242
0.82183 0.02866
0.78007 0.03540
0.73567 0.04249
0.68922 0.04975
0.64136 0.05696
0.59272 0.06390
0.54394 0.07020
0.49549 0.07546
0.44767 0.07936
0.40077 0.08173
0.35505 0.08247
0.31078 0.08156
0.26813 0.07908
0.22742 0.07529
0.18906 0.07037
0.15345 0.06448
0.12094 0.05775
0.09185 0.05033
0.06643 0.04238
0.04493 0.03408
0.02748 0.02562
0.01423 0.01726
0.00700 0.01100
0.00090 0.00245
0.00000 0.00000
0.00000 0.00000
0.00091 -0.00286
0.00717 -0.00682
0.01890 -0.01017
0.03596 -0.01265
0.05827 -0.01425
0.08569 -0.01500
0.11800 -0.01502
0.15490 -0.01441
0.19599 -0.01329
0.24083 -0.01177
0.28892 -0.00998
0.33968 -0.00804
0.39252 -0.00605
0.44679 -0.00410
0.50182 -0.00228
0.55694 -0.00065
0.61147 0.00074
0.66472 0.00186
0.71602 0.00268
0.76475 0.00320
0.81027 0.00342
0.85202 0.00337
0.88944 0.00307
0.92205 0.00258
0.94942 0.00196
0.97118 0.00132
0.98705 0.00071
0.99674 0.00021
1.00000 0.00000
|
| 1113.229 | 2500 airfoil library available commercially | GAUSS::REITH | Jim 3D::Reith MLO1-2/c37 223-2021 | Wed Dec 08 1993 11:43 | 16 |
| Last night while thumbing through the new RCSD I noticed that there's a
2500 airfoil library available from Germany for about $250. Have any of
our German noters heard anything about this? I'm considering buying it
but I'd like to hear comments on it before shelling out that much cash
sight unseen.
It's supposed to include all the Soartech airfoils and a bunch of others.
It said that updates were available so they seem to be trying to keep it
current. I'm still working on software that will use a 400dpi scanner
and generate a .foil style file from several scanned images (to average
out the scanning inconsistancies). I get a lot of paper templates of
"the designer drew this straight to the plans" requests for cores. The
nice thing about the hand scanner is that you can scan the airfoil from
leading edge to trailing edge and run as long as you'd like up to a 4"
thickness. You get good resolution when you run it in B&W line mode.
Just another project on the "to do" list.
|
| 1113.230 | Yes, it's there. Just have to dig... | KBOMFG::KLINGENBERG | | Wed Dec 08 1993 12:47 | 8 |
| Jim,
yes, this library is available, being updated and - I think - even
includes the plotting program. Maybe Joe has the info at hand. I will
look it up once Bernd returns the Aufwind and FMT mags I gave him at
lunch. Stay tuned.
Hartmut_catching_up
|
| 1113.231 | | GAUSS::REITH | Jim 3D::Reith MLO1-2/c37 223-2021 | Wed Dec 08 1993 13:24 | 5 |
| I'd be interested in any non-supplier reviews you've seen. I'm seriously
considering getting it since the current library isn't as complete as I
need. I'm not really interested in typing in all the Soartech airfoils
by hand and there have been a few I haven't had. This will be more of a
problem once I get the cutter going and using the files.
|
| 1113.232 | 2500 airfoils | FRUST::HERMANN | | Thu Dec 09 1993 06:10 | 68 |
| 1113.233 | Accurate construction views | UNYEM::BLUMJ | | Thu Dec 09 1993 12:43 | 38 |
| RE: -1
Joe T.'s point regarding accurate building is echoed by Dr. Michael
Selig himself. I remember reading an article in a magazine where
the builder(Bob Champine LSF V(twice!)) was complaining that the
difference between the SD7032 and SD7037 was "only a couple of
swipes witht the sanding block". In other words, very difficult
to reproduce accurately.
Selig replied to the letter stating that although it might appear that
such minor variations would be insignificant, the wind tunnel results
do not concur. He concludes by stating that building to accurate
tolerances is a difficult challenge, but feels that there are
significant performance differences resulting from innacurate
construction.
Another interesting tidbit I recently saw was the training that is
going on under Franz Weissgerber's direction. The author stated
that he witnessed a nine year old working unsupervised producing
molds of Weissgerber's old F3B design. He stated that the quality
(fit,finish, etc) was "near commercial quality".
I think the only thing that is holding back the commercial production
of very accurate models is demand. With CNC machinery, I would think
it possible to produce the necessary molds. Obviously the acquisition
and setup costs would be high. With the low demand for this type
of model, the selling price would remain high to offset the high
startup cost. If demand were greater, a venture of this type might
make some business sense.
I certainly agree with Joe T. that this level of accuracy would
probably only be noticed by the best flyers. It is a goal worth
striving for however.
Regards,
Jim
|
| 1113.234 | Rout away everything that looks like a wing and you have a female mold! | GAUSS::REITH | Jim 3D::Reith MLO1-2/c37 223-2021 | Fri Dec 10 1993 13:37 | 21 |
| I've done my homework on this some and for the most part. None of us
can afford to have a mold commercially made (don't forget you need a
left AND a right, top and bottom).
There are CNC devices that will control a Dremel with a burr bit. This
would be slow but one thing we can spend freely is time. The next issue
is the material to "rout out". You need something that will develop a
smooth hard surface. One thing I've considered is routing it out or
plywood oversized and then lining the mold with tooling coat and
rerouting to finished specs. This is about the cheapest method. I
calculated that it would take almost a full day to create the mold for
one panel in this method and then another day to buff it out to finish
quality. My guesstimates are ALWAYS optimistic. If they weren't, I'd
never get started on any elaborate projects.
I'd be interested in hearing what the resolution of the foil files are
that he's selling. I have no interest in buying 20 station foils at
that price. I'm hoping Santa will bring me the (now) 10 Soartech
manuals or at least the permission to spend the money. Sounds like
the $250 would be better spent on a scanner and some OCR software
(which I need for other things anyway)
|
| 1113.235 | Construction Rambling | UNYEM::BLUMJ | | Fri Dec 10 1993 17:58 | 37 |
|
I remember reading that Hans Mueller(a cottage German F3B Glider
builder of renown) spent over 1000 hours doing a wing mold. His
wife lays up the glass, they produce 1 ship per week.
I talked with Steve Neu about his visit to Weissgerber's facility.
He mentioned that Weissgerber is milling molds out of solid blocks
of a composite material using CNC equipment. I guess his ships are
about as good as they get(He still loses to a couple of Americans
every year with the relatively crude Se-X models made in Neu's garage
though!)
I talked extensively with Swiss Martin Baemert at KRC this year.
Soartech 10 will include an comprehensive article on composite construction
authored by Baemert with over 60 photos providing a step-by-step
primer on building an all molded airplane. Martin claims they are
now flying at speeds approaching 200 mph with these planes on
Swiss slopes! This sounds like a great reference.
Ex British F3B member(current team manager) Stu Blanchard produces
an F3B plane(Calypso) which advertises a wing profile with +/- .1mm
accuracy. I have seen no documentation on his construction methods,
although his move from foam and obechi to all composite is recent.
With my limited time/skills, moulding seems a long term goal. I hope
to experiment in the near future with "wet layup" of composites over
foam cores using mylar and my plywood mechanical press. Leading edges and
wingtips remain difficult obstacles for me. Just can't seem to get
interested in vacuum bagging, definitely a mental block!
I wish there was a "medium tech" offering between obechi/foam and
all moulded construction. The Freudenthaler Surprise is pretty
close to this(light/strong, medium price, possibly home producible).
|
| 1113.236 | winprof - airfoils for windows | FRUST::HERMANN | | Thu Dec 16 1993 07:53 | 43 |
| REPLY TO .229:
hi all,
i got the demo version of winprof - profile for windows, professional
version. some remarks:
the software is in german. hitting ctrl-b might(!) switch it to english.
the help text and the explanations to the foils remain german however.
the limitations imposed on the demo are a very small foil database, that
can not grow over 20 foils, and you can not create another database.
everything else should work. the spar support is new, and still not very
elaborate.
no support for postscript or ink-jet printers, unless they emulate epson.
the option "gedehnte Darstellung" will amplifiy the y-values by 10. this is
to detect imperfections in the y-distribution.
the software leaves a good impression.
coming to the database:
yes, there are 2400-2500 foils in it. too much to list.
at least 400 of them are goettingen, 40 hq, 175 eppler, 50 s/sd, >450 naca...
if you want to know if a specific foil is included, ask me offline via mail.
the foils have and are beeing collected by mr. bender, a known name in the
foil business. interesting is: the foils come together with a comment,
suggested use, source, polars and a calculated speed distribution. the polars
are not calculated, the data is entered into the database from other
sources. all foils are normalized around the chord-line, and are in a range
from 0.0 - 100.0 (opposed to the 0.0 - 1.0 normalization for the af-prog).
a translated version will be made available and distributed through, - guess
who - herk stokely.
a user review about the windows version (not the professional version) will
appear in the january FMT, written by mr. bender.
the demo version can be copied from:
FRUST::Disk$Scratch:[Public]Winprof.Zip
copy it to a pc (nft copy /Block), unzip it, copy the files to a floppy and
install this floppy from windows.
enjoy, merry christmas, lots of airplanes and a crashfree '94
joe t.
|
| 1113.237 | More questions | GAUSS::REITH | Jim 3D::Reith MLO1-2/c37 223-2021 | Thu Dec 16 1993 11:56 | 26 |
| Epson emulation doesn't give me warm fuzzy feelings about the resolution.
Joe, can you check and answer the question about the number of points in
the .foil files. Having these airfoils is good but not at 20 point
resolution.
BTW: stating >450 NACA airfoils is misleading. These airfoils are easy to
generate since the fixed datapoints get manipulated in straight forward
methods. This is done by the current af32.com If people are interested,
it would be easy to write a conversion program that took the algorithm and
massaged the files into usable .foil files directly. You're just changing
the camber, max thickness and percentage of chord for max thickness.
Are any of the SD9xxx airfoils out there?
I'm probably going to go with a scanner (which I need for getting airfoils
off plans), some OCR software (probably Omnipage on the Mac), and copies
of Soartech. Realisticly, I get requests for less than 30 different
airfoils and just need the capability to input (even manually) new ones on
demand. The scanner software to generate .foil files from templates on
plans will prove much more useful.
FYI: Scanning and OCR are two destinct operations in most cases. The
scanner generates a .tiff (or similar) file and the OCR software uses that
as input. This then allows me to scan on the DOS machine where the hardware
is cheap and OCR on the Mac where the UI is better. Sneakernet works great
for transferring the files.
|
| 1113.238 | winprof - more answers | FRUST::HERMANN | | Thu Dec 16 1993 12:58 | 32 |
| >Joe, can you check and answer the question about the number of points in
>the .foil files. Having these airfoils is good but not at 20 point
very many foils come with 33 points, but these are the older ones. then there
are 50, 60, 70, 80, 90 points, with 60 - 90 for the more "modern" foils.
i think - i am not sure - that these are the x-stations, so you get twice
as much y-stations. look at the rg15 in the demo, the catalog say's it has
62 points.
wiechers explained to me, that most of the very old foils have been smoothed,
thus resulting in more points, even if the sources had less. during the
smoothing he also looked at the speed distribution. if this was jerky, he
corrected the points a bit, until the speed distr. and the "gedehnte
Darstellung" (expanded view) was looking "smooth"
>BTW: stating >450 NACA airfoils is misleading. These airfoils are easy to
>generate since the fixed datapoints get manipulated in straight forward
of course you can calculate the NACA-foils.
but as you have data stored (polars, l/d?) along with the foils, every NACA-
foil is stored separately.
>Are any of the SD9xxx airfoils out there?
sorry, no.
>scanning and ocr
my idea was to scan in the tables defining a foil, then ocr-ing them,
resulting in a new foil-file.
cheers
joe t.
|
| 1113.239 | | GAUSS::REITH | Jim 3D::Reith MLO1-2/c37 223-2021 | Thu Dec 16 1993 13:11 | 5 |
| Since I'm not running Windows on my DOS machine, I won't really be able
to check out the program. Joe, since you have af32/40 and the demo, could
you compare the two copies of the rg15 and comment. If he's using full
resolution Soartech info, they should be the same. Just curious 8^)
|
| 1113.240 | Looks like I'll OCR from Soartech | GAUSS::REITH | Jim 3D::Reith MLO1-2/c37 223-2021 | Mon Dec 20 1993 18:45 | 7 |
| Saturday I bought the scanner. I got a Logitech Pilot 32 gray scanner
with image editor and OCR software for DOS. Plugged it in and it runs.
It has a 1 bit line art format that will be great for scanning airfoils
from plans and it outputs .tif files which I have routines that will
decode it for me so I should be able to generate .foil files from the
scanned images in a little while. The scanner WITH the OCR software
(Catchword) was $99 at BJ's Wholesale Club.
|
| 1113.241 | Wow, cheap. | QUIVER::WALTER | | Mon Dec 20 1993 19:06 | 5 |
| You got a scanner for $99??? Is it one of these hand operated jobs,
looks sort of like a high-tech paint roller? Good deal.
Dave
|
| 1113.242 | The price sure caught my eye | GAUSS::REITH | Jim 3D::Reith MLO1-2/c37 223-2021 | Mon Dec 20 1993 19:13 | 10 |
| Yep 4" 100-400dpi for DOS. The same one for my Mac was $269! Seems to
work pretty well for my needs. Now to decode the scanned images into a
.foil file...
From what I've heard, for the stuff I'm doing, the 32 gray scanner is
better than getting a 256 gray or color since the sensors are simpler
and more reliable. I was just pleased to see it work well. For quality
scanning you need to track along a straight edge but it wasn't bad
freehand.
|
| 1113.243 | Describe a .foil file Please | ANGLIN::BEATTY | | Mon Dec 20 1993 20:29 | 4 |
| What is a .foil file?
Will
|
| 1113.244 | A set of datapoints defining an airfoil (this is a standard format posted in journals) | GAUSS::REITH | Jim 3D::Reith MLO1-2/c37 223-2021 | Tue Dec 21 1993 10:48 | 10 |
| A .foil file is used by the af32 program to plot an airfoil. Most people
just use the provided library and never see them but if you extract an
airfoil from the library, it has the form of the coordinate pairs in
1113.228. Putting this set of coordinates in a file e387.foil would
allow the program to use it. The program then draws splimes between the
points which approximate the airfoil shape. My scanner program will
generate these points from a scanned template so I can print out scaled
template, compensate for sheeting, or drive my cutter directly (I've
written software that converts from this format into stepper motor
commands).
|
| 1113.245 | Help printing 16" airfoil | MISFIT::BLUM | | Thu Jan 20 1994 13:04 | 17 |
| I am attempting to print an airfoil with 16" chord using the af32.com
program. I am outputting to an LPS20 with 11"x17" paper in the middle
tray using the following command:
print/que=XXXXXXX/param=(input_tray=middle,sides=1) naca2425_16.ps
The airfoil prints out on the 11"x17" paper, but it starts printing
nearer the middle of the page and cuts the airfoil off just as if
it were printed on 8.5" x 11" paper.
Anybody know what I'm doing wrong?
Thanks,
Jim
|
| 1113.246 | | SNAX::SMITH | I FEEL THE NEED | Thu Jan 20 1994 13:49 | 5 |
| Jim,
If you hold the page up and down (verticle), which way did the foil
print, verticle or horizontal. You may have to use the LANDSCAPE
qualifier.
|
| 1113.247 | | VMSSG::FRIEDRICHS | APACHE::FRIEDRICHS | Thu Jan 20 1994 15:20 | 7 |
| Jim, this is the problem that I had as well... I never did resolve
it.. Joe H. is working on AF40 which does work correctly...
Joe, any progress?? How about letting out a FT version??
jeff
|
| 1113.248 | Trevor's fix? | UNYEM::BLUMJ | | Thu Jan 20 1994 17:08 | 18 |
| RE: -1
Jeff,
I did read your note describing the same problem, but a subsequent
note by Trevor provided a solution. I have not been able to try it
since our LPS20 went down this morning.
He suggested editing the ".ps" file with the following line:
[1.0 0.0 0.0 1.0 0.0 360] contact - see note 1113.226
Did you try this?
Thanks,
Jim
|
| 1113.249 | | GAUSS::REITH | Jim 3D::Reith MLO1-2/c37 223-2021 | Fri Jan 21 1994 11:23 | 4 |
| I have found that the RG12a airfoil in the library is screwed up. It
prints a reasonable sawtooth wave at home and hangs our LPS20 here.
Does anyone have the coordinates handy? I need these for a customer
ASAP
|
| 1113.250 | I might | UNYEM::BLUMJ | | Fri Jan 21 1994 11:34 | 9 |
| Jim,
I believe I have them at home. Will check and post Monday.
Regards,
Jim
|
| 1113.251 | Thanks in advance | GAUSS::REITH | Jim 3D::Reith MLO1-2/c37 223-2021 | Fri Jan 21 1994 12:02 | 7 |
| Jim,
Well, it looks to me like the leading zeros on the decimals have been
removed giving an interesting effect. I editted the .foil file and am
trying to print them again. Would it be possible to call you tomorrow
to go over them? I need to cut these wings this weekend. I can update
the copies I have at home and print them there.
|
| 1113.252 | I fixed the leading zeros and this one works - the initial comment isn't mine | GAUSS::REITH | Jim 3D::Reith MLO1-2/c37 223-2021 | Fri Jan 21 1994 12:22 | 64 |
| %Here is the RG12A but I dont think it is correct...
1.00000 0.00000
0.99665 0.00059
0.98703 0.00246
0.97194 0.00551
0.95179 0.00921
0.92666 0.01325
0.89678 0.01766
0.86258 0.02238
0.82453 0.02731
0.78310 0.03232
0.73879 0.03730
0.69213 0.04212
0.64368 0.04674
0.59393 0.05104
0.54340 0.05487
0.49264 0.05809
0.44217 0.06058
0.39250 0.06222
0.34413 0.06294
0.29752 0.06267
0.25311 0.06138
0.21131 0.05906
0.17248 0.05573
0.13697 0.05143
0.10506 0.04625
0.07702 0.04030
0.05306 0.03373
0.03339 0.02671
0.01810 0.01942
0.00735 0.01226
0.00100 0.00531
0.00000 0.00000
0.00354 -0.00389
0.00953 -0.00703
0.02204 -0.01138
0.03760 -0.01484
0.05756 -0.01793
0.08143 -0.02053
0.10918 -0.02266
0.14059 -0.02434
0.17548 -0.02560
0.21358 -0.02646
0.25462 -0.02696
0.29829 -0.02711
0.34421 -0.02694
0.39199 -0.02647
0.44119 -0.02569
0.49132 -0.02461
0.54192 -0.02318
0.59248 -0.02135
0.64260 -0.01890
0.69148 -0.01559
0.73816 -0.01184
0.78233 -0.00827
0.82366 -0.00517
0.86166 -0.00266
0.89589 -0.00084
0.92587 0.00030
0.95113 0.00085
0.97147 0.00092
0.98682 0.00064
0.99661 0.00022
1.00000 0.00000
|
| 1113.253 | Call me if you need them | UNYEM::BLUMJ | | Fri Jan 21 1994 12:50 | 9 |
| Jim,
I think the RG12/12a coordinates were listed in an old edition
of Silent FLight. If you still need them this weekend my home
phone is (716)367-2911.
Regards,
Jim
|
| 1113.254 | The crisis is passed but we should double check the values I just posted | GAUSS::REITH | Jim 3D::Reith MLO1-2/c37 223-2021 | Fri Jan 21 1994 13:03 | 6 |
| Thanks Jim. I think the templates I just printed will do for now. How
about taking a copy of .252 home and double checking them for accuracy?
The original poster put a comment at the top that seemed to indicate
there was some question.
I'm real interested in your exploits with the painted wings.
|
| 1113.255 | writing the af40 user guide | FRUST::HERMANN | | Mon Jan 24 1994 05:44 | 24 |
| > I am attempting to print an airfoil with 16" chord using the af32.com
> program. I am outputting to an LPS20 with 11"x17" paper in the middle
> The airfoil prints out on the 11"x17" paper, but it starts printing
> nearer the middle of the page and cuts the airfoil off just as if
> it were printed on 8.5" x 11" paper.
> Anybody know what I'm doing wrong?
hi jim,
you aren't doing anything wrong. af32 has a hardcoded reference to the
paper size. af40 hasn't.
yes, i know, i am late. as a matter of fact, i started last weekend to
work on the user guide of the new version. its still a lot to write, explain
and even draw some pictures. but it's high on my priority list now,
as i finished building a glider that i've been working on for a decade
(intermittent of course....)
jim, if you still need that 16" printout, contact me.
cheers
joe t.
|
| 1113.256 | No hurry-Thanks | MISFIT::BLUM | | Mon Jan 24 1994 12:37 | 12 |
| Hi Joe T.,
Looking forward to AF40, I am in no hurry for the 16"
airfoil. Trying to kit bash a Senior Telemaster to piggyback
1/4 scale gliders.
What glider did you build?
Regards,
Jim
|
| 1113.257 | Gremlin airfoil | KAY::FISHER | High Tech Red Neck! | Wed Jan 26 1994 16:28 | 12 |
| Is the Gremlin airfoil in the library?
If not could someone (Jim Reith) please put it in?
I've always wanted to try and cut a 1 piece wing and I
need to be able to draw a set of tapered foils with
the root artificially large (a projection).
Bye --+--
Kay R. Fisher |
---------------O---------------
################################################################################
|
| 1113.258 | It's all based on a hand drawn airfoil currently | GAUSS::REITH | Jim 3D::Reith MLO1-2/c37 223-2021 | Wed Jan 26 1994 16:31 | 6 |
| You could use a NACA airfoil since it's symetrical. I don't have one
generated and I never really checked where the maximum thickness was
on the original napkin 8^)
I will have one in the future as I convert to the automatic cutter
but I'm a week or two from that.
|
| 1113.259 | Spitfeuer. | CSTEAM::HENDERSON | Competition is Fun: Dtn 297-6180, MRO4 | Wed Jan 26 1994 17:35 | 12 |
| In almost the same vein; I just read an article in a British scale mag
where a guy has built a 1-1 Spitfire. He used a Jaguar V-12 car engine.
He too had to get the root and tip incidences just right on the full size
eliptical wing.
The thing flew just great and is the best TOY that I have seen in years.
I was amazed and just a little envious. I am so glad that here are
people out there that do these things.
E.
|
| 1113.260 | Soartech 8 Data on floppy | RGB::MINER | Dan Miner, DTN:225-4015, HLO2-1/J12 (@ H11) | Thu Mar 17 1994 13:41 | 17 |
| Jim - The Soartech 8 airfoils and windtunnel data is available from
Mr. Fraiser for $15. (I think). I have one.
The 16" airfoil can be printed on the LPS20 with a fairly simple
Postscript command added. However, in a fit of electronic
housecleaning, I seem to have deleted the information.
_____
| \
| \ Silent POWER!
_ ___________ _________ | Happy Landings!
| \ | | | | |
|--------|- SANYO + ]-| ASTRO |--| - Dan Miner
|_/ |___________| |_________| |
| / | " The Earth needs more OZONE,
| / not Castor Oil!! "
|_____/
|
| 1113.261 | Hi Dan | LEDS::WATT | | Thu Mar 17 1994 14:37 | 5 |
| Dan,
Good to hear from you! You have been very quiet lately.
Charlie
|
| 1113.262 | Printing BIG chords | SHIPS::HORNBY_T | Soarers are rarely Silent | Fri Mar 18 1994 11:34 | 37 |
| Dan re-2.
The answer I published (not necessarily the only one) is 1113.226..
But not wishing to miss the opportunity here it goes again..
PS. Thought for even bigger chords..
By the way the if you wanted foils greater than 15.5" chord you could
fiddle with the '360' and print with two different thus shifting the image
on the paper and then stick the two pieces together.
---------+++---------------
FOR PRINTING LARGER FOILS REQUIRING A3 paper. (10.5"-15.5")
o process the foil you require as normal using the AFxx.COM
o edit the ".PS" file which is generated by adding the following line
straight after the comments section at the top of the file. i.e.
after the lines stop beginning with "%"
[1.0 0.0 0.0 1.0 0.0 360] contact
this will shift the image on the paper by 5"
o print the new edited file on your postscript printer which has A3
capability e.g.
$ Print/que=QUENAME/param=(page_s=A3,page_o=landscape) FILENAME.ps
Regards
Trev
|
| 1113.263 | who is going to use af v4.0 if no one remains | FRUST::HERMANN | | Mon Sep 26 1994 07:11 | 41 |
| dear fellow modellers,
as i am looking onto my calendar, i see approaching a date that might be a
sad one for all of us. as i do not know the details of the quantum contract
i am not sure if some of you will still be able to participate in this
notes conference next week.
if this really would be the fact, i could imagine the possibility of a
phanthom conference on the quantum side. mail servers could update the
conference on both sides. i dunno if there is already existent software
that accomplishes this, or if maybe it isn't allowed by some policy.
but there is life after dec (maybe even better?!) and to sweeten the
departure (if taking place at all) i will announce
A I R F O I L V4.0 ! ! ! ! !
the release notes are contained in the next reply, the user guide is within
the kit.
i hope the software is as bugfree as i think it is (murphys law: there is
always one more bug than you expect...) and that the new features are
really the stuff you ever wanted to have but didn't dare to ask....
i will be in the office on wednesday evening (if the body guards let me in),
to answer possible questions.
everybody who will not have notes access in the future, and who will be
using AIRFOIL, should send me a mail. i will then put together an update list.
have fun with it!
cheers
joe t.
p.s. would there be interest for a dos version as well?
p.p.s. my internet addresses for further mails are:
hermann@frust.enet.dec.com
hermann@frais.enet.dec.com <-- official all-in-one cluster
|
| 1113.264 | af v4.0 release notes | FRUST::HERMANN | | Mon Sep 26 1994 07:15 | 116 |
|
AIRFOIL 4.0 Release Notes
AIRFOIL 4.0 comes with a lot of new features:
o Bow cutting marks
o Chordline
o No program restricition on paper size - only the printer is the limit
o Multiple spars
o A choice of different spar geometries: Rectangular, Round, Tapered
o Many diffrent possibilities to position the spar within the ribs
o Boxes around ribs for foam cutting templates
o Parameter file, for easy creation of similar rib sets
o Enhanced User Guide
o User interface can be customized to reflect your personal defaults
o User interface can be switched to inches and mm
o Doubled the number of airfoils in the library
o Airfoils with x-values from 0.0 to 100.0 can be processed
o Convert airfoil data into DXF-format for exchange with CAD-programs
The standard AIRFOIL user interface was extended, but you only have to
answer "0" to very few questions to switch off the new features.
o Copying and installing the kit
Create a new directory for the AIRFOIL software. Move into this
directory and issue the following command:
$ COPY FRUST""::AF040.SAV *
Other locations are:
$ COPY FRAMBO""::AF040.SAV *
$ COPY FROCKY""::AF040.SAV *
Now unpack the kit:
$ BACKUP AF040.SAV /SAVE /LOG *
You should see the following files beeing extracted/created:
AIRFOIL.COM
AF040.RELEASE_NOTES (this file)
AF040_UG.PS
AFCVT.COM
AF_DXF.COM
AF_EXTRA.COM
AIRFOIL.TLB
You can now delete the kit and print the user guide on your favorite
printer. See the section "Before we really start" in the user guide
before starting AIRFOIL the first time.
This completes your installation. AIRFOIL is now ready to use.
o Naming conventions for airfoils in the library
A great effort has been made to update the airfoil library. Double
and triple definitions of airfoils have been deleted in favour of
airfoils that carried a comment defining their original source. Some
airfoils have been corrected, as long as the original source was
available for comparison. All airfoils have names not exceeding 8
characters. This modification eases the exchange of foil files
across different computing platforms.
If the original source showed off less data pairs than the actual
airfoil, then the airfoil is smoothed and carries a trailing "_S"
or "S", as the name length restriction permits.
If comments in the airfoil indicated some deviation from the original
data, then the airfoil is modified and carries a trailing "_M" or "M".
Modified airfoils also resulted from changes of the front- or aftmost
data pairs, when they did not meet exact x-values of 1.0 or 0.0.
Some airfoils had names with characters that inhibited their use,
because it is not possible to extract airfoils with a name of
"HQ2.5/9" from the library. In general airfoils now have only
characters, numbers and an underscores in their names. The former
airfoil now has the name of "HQ2509".
o New file type for extenal foil files
The file type for AIRFOIL 4.0 external foil liles has changed from
"FOIL" to "FOI". Rename your old foil files to reflect this new file
type. The change has been introduced to ease the exchange of foil
files across different computing platforms.
o Hole elevation
The hole elevation parameter is now an absolute value.
o MIN parameter for spars
The MIN parameter does not work very good on flat bottomed airfoils..
I can make no guaranties about copyrights. I found many of the foil files
on a FTP-directory. So i think it is safe to assume, that the foil files are
either in the public domain anyway or they are free as long as they are not
used commercially.
The author can be reached by
DECnet:
Joerg Hermann @FRS (All-in-one)
Hermann::FRUST (VMS-Mail)
or by Internet:
Hermann@FRAIS.ENET.DEC.COM (All-in-one)
Hermann@FRUST.ENET.DEC.COM (VMS-Mail)
Have fun and fly!
|
| 1113.265 | more foils to come | 30411::REITH | Jim Reith - racores@world.std.com | Mon Sep 26 1994 11:14 | 5 |
| I have been gathering airfoils in this format for some time. Before I move on
this week I'm going to make them available to this program. I have found several
popular airfoils to be missing from the af32 library.
Jim
|
| 1113.266 | DOS? | CXDOCS::TAVARES | Have Pen, Will Travel | Mon Sep 26 1994 14:33 | 2 |
| Did I hear someone refer to a DOS version????? Since I'm on my way
out, I'd like to bag a copy if it exists.
|
| 1113.267 | | 30411::REITH | Jim Reith - racores@world.std.com | Mon Sep 26 1994 15:05 | 3 |
| I'll mail you a pointer on the net. It's by one of my customers...
Jim
|
| 1113.268 | Problem with AF040 | 35989::BLUMJ | | Thu Sep 29 1994 13:53 | 21 |
| First of all, many thanks to Joe T. for all the great enhancements
implemented in AF040. Great Job! This is now a very professional
tool for producing airfoil templates.
I have experienced a problem trying to use the "box" feature. I
enter a box width greater than the root chord(example root=8 inches,
box width=10 inches), but the program never prompts me for a box
height and the box and the airfoil are not drawn when I print the
foil.
Anyone else seeing this problem? Am I doing something wrong or is this
a bug?
Thanks.
Regards,
Jim
|
| 1113.269 | | 30411::REITH | Jim Reith - racores@world.std.com | Thu Sep 29 1994 13:58 | 10 |
| Because of the craziness of this week, I have not had a chance to upload the
airfoils I have. If someone is willing to post/insert them, I'll email them to
you. I just haven't had the time.
Joe,
Would you be willing to do this? Could you mail me a listing of names of what
you currently have in the library?
Jim
|
| 1113.270 | first error in af040 discovered... | FRUST::HERMANN | | Tue Oct 04 1994 08:29 | 21 |
| hi jim,
i fear you discovered an error.
but otoh, i cannot reproduce the fact that af is not asking for the
box height if i entered a boxwidth other than 0.
did you change the units as described in the ug if you are using inches?
check the parameter section within the produced .ps file for the following:
/offset_box_le_tip def <-- dbl space, should be: /offset_box_le_tip 0 def
/rib_alignment 0 def
/dist_box_rib def <-- dbl space, should be: /dist_box_rib 0 def
if you have the dbl space problem as above, enter a 0 there and try again.
this should at least help you in printing.
to analyse things further i need a copy of your .ps file.
cheers
joe t.
|
| 1113.271 | workaround for fractional boxwidth | FRUST::HERMANN | | Tue Oct 04 1994 12:47 | 16 |
| hi all,
the reason for the error described by jim blum is the use of a fractional
boxwidth. at the moment this is not supported, and the program thinks, you
entered a 0 - hence you are not asked for the boxheight.
workarounds:
enter a non-fractional boxwidth rounded to the next integer,
or enter a non-fractional boxwidth and change it to have the fractional part
the resulting .ps file. this works, as it is only a limitation of AIRFOIl.COM.
cheers
joe t.
ps: add a coment to the ug: boxwidth must not be entered with a fractional
part. (for the time beeing).
|
| 1113.272 | It works! | 35989::BLUMJ | | Tue Oct 04 1994 16:14 | 9 |
| RE: -1
Thanks, it works fine now! I really like the enhancements to this
program, it will make template production go much quicker.
Regards,
Jim
|
| 1113.273 | Airfoil Ramblings | RANGER::REITH | | Thu Oct 20 1994 10:41 | 35 |
| Last night I met with one of my customers to give him his recent order. He's
into HLGs almost exclusively. We talked a bit and then he gave me 3 photocopied
pages from a new magazine, Quiet Flight (I believe). I'd be interested in
getting subscription information to this. I was told it's produced by a former
employee/publisher/editor/writer of Silent Flight that decided he/she could do a
better job. Anyway, if they do this sort of article, I'd subscribe.
The article was by Michael Selig about the development of his latest airfoils.
Yes, I now have coordinates and will share them in the near future (read: once I
get them scanned/typed in). In the article he talks about the compromises they
used in getting the airfoils put in. The airfoils, by the way, are S7012, for
F3B as an RG15 improvement, S4083, as a better HLG airfoil when compared to the
E387/SD7037, and a S7055 which is a thick flat bottomed airfoil for better
characteristics in the slow trainer market.
The article goes into a lot of detail in the process Selig went through in
interpreting his conversations with Joe Wurts and Mike Lackowski about F3B
performance. He also talks about airfoil performance ranges in the "compressible
jelly" paradigm where if you improve performance in one area, it gets worse
elsewhere. He panned the SD7003 airfoil as having the performance problems right
about where the typical F3B ship needed them and used the RG15, SD7003, and
S2048 as comparison airfoils. He pretty much stated that for current tasks the
RG15 was about the best all around airfoil available and that for specific F3B
tasks the new S7012 was an improvement in the typical F3B task envelope. He did
mention that the improvements were in a small speed range and that a poorly
flown airplane might actually perform worse. He also mentioned that for typical
thermal tasks, the SD7037 was probably the best performing "forgiving" airfoil.
The S4083 was supposed to give less drag during the higher speed launch phase
and have better upwind penetration in higher wind conditions. He mentioned that
he felt the E387 and SD7037 were better in low to medium wind conditions where
penetrations wasn't the primary concern (sounds like we need one of these for
Tornado Al's next contest)
Very interesting article, albiet, quite technical.
|
| 1113.274 | | RANGER::REITH | | Fri Oct 21 1994 10:36 | 9 |
| You know, the majority of the new airfoils came from a DOS program from the
USENET as freeware (from one of my customers) and since I have a PC sitting on
my desk... I brought the program in and will do the transfer while waiting for
compiles. I can also make this program available if anyone wants to play with
it. I haven't used it much so I can't really comment on it. I have had some
problems getting it to accept a .foil file even through the format is very
similar to it's .af format.
Jim
|
| 1113.275 | | CXDOCS::TAVARES | Have Pen, Will Travel | Fri Oct 21 1994 14:41 | 6 |
| I tried it out, but for some reason it doesn't like my video adapter.
When I move the mouse around the screen, it leaves a trail that messes
up the display. I've had this happen before with DOS programs, and
usually have had to give up on the program. Other than that, its
super-slick and I recommend it to anyone, expecially those who won't
have access to our program in a very short time.
|
| 1113.276 | | RANGER::REITH | | Fri Oct 21 1994 16:38 | 5 |
| I had problems with it at home as well but it seems much better here at work.
I'm going to keep at it until I get everything straightened out and then I'll
post an updated af40 library.
Jim
|
| 1113.277 | | CXDOCS::TAVARES | Have Pen, Will Travel | Mon Oct 24 1994 14:09 | 7 |
| Jim, do you know the fellow who wrote the program? I've been meaning
to return my comments to him, but haven't gotten to it. I don't think
the problem is as much with his program as it is with my wonderful DEC
multi-sync monitor, or should I say boat anchor. Must've been made at
the same place where they make K&B .20 Sportster engines. Anyway, I'm
interested in seeing the next version; maybe that problem will be
fixed.
|
| 1113.278 | Here's the info I have. Don't know if it's current. | RANGER::REITH | | Mon Oct 24 1994 17:01 | 7 |
| The snailmail address I have for him is:
Andrew J. Westreich
1431 Bell Oaks Lane SW
Rochester, MN 55902
and the email address listed is ajw@apollo.mayo.edu
|
| 1113.279 | | RANGER::REITH | | Wed Jan 18 1995 17:22 | 8 |
| I just tried to use airfoil 4.0 to print out a 7.5" SD8020 with no leading or
trailing edge, 1/32" skin thickness, chord line and 10 bow marks. It printed out
.25" chord. Has anyone else seen this? I looked through the .ps file and it
seemed fine and all the parameters were right in the data section. Did I miss an
update that fixed something like this? (SD8020 is a 0.0-1.0 .foi file so I
suspect something in the foil range detection but can't spot it in the code)
jim
|
| 1113.280 | | RANGER::REITH | | Wed Jan 18 1995 17:26 | 2 |
| Oh yeah, I just mailed the file to myself and the DECWindows mail program
displays it tiny as well...
|
| 1113.281 | af 4.0 uses milimeters | FRUST::HERMANN | | Thu Jan 19 1995 07:35 | 14 |
| hi jim et al,
af 4.0 uses milimeters as default measurement unit (i'm german...)
i have explained in the manual how to change the default.
a quick fix now is:
search the ps-file for: unit_factor 72 25.4 div def
delete: 24.4 div
save and print...
rtfm :-),
joe t.
|
| 1113.282 | | RANGER::REITH | | Thu Jan 19 1995 10:45 | 10 |
| Not very user friendly if I have to RTFM 8^)
I figured it was just a feature enhancement update. Yeah, I'll pull the manual
and read it since you took the time to do it. I'll probably pop the div out
anyway since most of the requests I get are in "english" units (yeah, blame the
British 8^)
Thanks for the workaround.
Jim
|
| 1113.283 | | FARAN::kurik.reo.dec.com::noddle | | Fri Jan 20 1995 08:43 | 21 |
| Hey don't blame us! It was the "europeans" who had problems
with their 12-times table and so invented "metric"! What was
wrong with 12" to the foot, 3' to the yard and 1760 yds to
the mile? Come think of it, what was wrong with 12 pennies
to the shilling and 20 shillings to the pound (or 240
pennies if you prefer)? ...OK, now you mention it... ;-) ;-)
Actually we've almost moved to the metric system -
however, distances are still measured in miles and where
else could you buy 2"X4" timber in 2 metre lengths? Or what
about a 4'X8' sheet of 15mm MDF? And where would plumbing be
without 3/4" to 15mm adapters? Still, most things are shown
in "bi-lingual" units, so we'll get there in the end -
maybe.
Keith.
P.S. FWIW, I like the simplicity of the metric system and
mostly use mm over inches when measuring. The problem I find
is in visualising what 127mmX203mmX1524mm looks like,
whereas 5"X8"X60" gives me no problems...
|
| 1113.284 | | RANGER::REITH | | Fri Jan 20 1995 11:09 | 6 |
| Thanks Keith, I almost died laughing at that one. Glad to see some humor out
there. I can picture a millimeter and a meter but I have to do the conversion
for 34cm. I love the concept of a 2 meter 2x4 8^)
Jim (who almost had his thumbs removed in college so he could count in octal 8^)
|
| 1113.285 | | RANGER::REITH | | Fri Jan 20 1995 11:13 | 3 |
| Oh yeah, I've got a case where it bit me as well. 11 years ago I bought a Volvo
245 wagon. It's metric... even the trunk... 43" side to side, 2 meters deep,
perfect for those metric sheets... available on the other side of the pond 8^(
|
| 1113.286 | Octal | GAAS::FISHER | BXB2-2/G08 DTN 293-5695 | Mon Jan 23 1995 15:00 | 11 |
| >Jim (who almost had his thumbs removed in college so he could count in octal 8^)
I always thought of it as 8 fingers and 2 index registers :-)
Bye --+--
Kay R. Fisher |
---------------O---------------
################################################################################
|
| 1113.287 | | VMSSPT::FRIEDRICHS | Ask me about Young Eagles | Thu Jul 11 1996 16:44 | 6 |
| does anyone have a copy of AF40.SAV?? I can't seem to find my copy of
it..
Thanks,
jeff
|
| 1113.288 | af040 supported from germany | FRUST::HERMANN | | Mon Jul 15 1996 07:12 | 10 |
| hi jeff et all,
i am still around and still supporting af040 if anyone should need it.
but hurry up, i think "they" are trying to sell si again, although
the last deal with eds didn't work out.
take your copy of af from frust:disk$in:[hermann.rc.af]af040.sav
cheers
joe t.
|
| 1113.289 | | VMSSPT::FRIEDRICHS | Ask me about Young Eagles | Mon Jul 15 1996 12:56 | 4 |
| Great, thanks!!
jeff
|
| 1113.290 | PC Airfoil? | CHEFS::HORNBY_T | Soarers are rarely Silent | Wed Oct 30 1996 18:36 | 9 |
| 1113.291 | plotting airfoils from pc | FRUST::HERMANN | | Thu Oct 31 1996 06:53 | 29
|