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Finding Airfoil Data For Amateur Projects?
An anonymous reader asks: "I am an aerospace engineering student who is engaged in an amateur project. A major hurdle I am having is finding modern airfoil data which can be used for a non-profit project. As most aerospace engineers know, just about all modern airfoil data are guarded industry secrets, so building an amateur project that requires precise airfoil data is difficult, because of the lack of available modern information. There is plenty of dated airfoil data from the 1960s or earlier, but my project requires access to modern data. Note that I do not have access to a wind tunnel to procure this data on my own. Where would one find free modern airfoil data for use in an amateur project?"
Maybe if you ask your manager nicely you will be able to take some old data home to play with it in the context of yoru project?
Paul B.
Could someone explain exactly what airfoil data is? I can conjure up some ideas, but IANAE.
symetrix. We are building a religion, a limited edition.
There's a great GPL'd program out there called XFoil that contains a large database of standard airfoils, including several "flat bottomed" foils, that are easy to construct from balsa.
I've used these before in some simple hobby projects (that never actually got finished)
Did you miss the memo?
NASA
If all this should have a reason, we would be the last to know.
Here's a pretty good site with coordinate data. I used it for a Catia model once. If you want data on the performance of the airfoil as well, such as polar curves, here is another site. Anyways, one thing to take note of is that not all modern airplanes use modern airfoils. For example, the Gulfstream GIV uses a modified NACA airfoil.
Do not go gentle into that good night. Rage, rage against the dying of the light.
Sailplanes are a good place to start. Get a copy of "Fundamentals of Sailplane Design" by Fred Thomas, printed by the college park press in MD. ISBN: 0966955307. It has a bunch of equations you are probably sick of (Stokes anyone?) and wing profiles and data for some gliders, including the Eta Uberglider.
If L/D is all you need, it should be easy, though there are some other numbers in the book that are probably useful. Good luck! Also, it never hurts to ask...Have you tried the military? Sometimes they give up random tidbits of data without a FOIA request.
Sig (appended to the end of comments you post, 120 chars)
Somebody report that guy to the FBI.
hmm try googling xplane. the end.
moox. for a new generation.
The book that I always pull off my shelf is the classic "Theory of Wing Sections" by Abbott and von Doenhoff (ISBN: 0486605868). It's a compilation of NACA data (NACA is NASA's predicessor) and the most comprehensive reference on the subject that I know of. Amazon has a new copy for $14.
I'm not sure why modern data would be a must for any non trans/supersonic vehicle (and some supersonic aircraft still use the classic NACA 4-digit airfoils).
This discussion (Free Hydro/Aero-Dynamic Software Simulators?) has some [maybe] useful links in it.
So much to do, so little bandwidth.
--
Try Mozilla
Oh you get all worked up about an AC account, but I bet you didn't even vote in the last election.
This is America, damnit. Speak Spanish!
If you're close enough to come to Prescott, AZ I have a feeling my university (Embry-Riddle Aeronautical University) would let you peruse our hundreds of volumes of data that NASA has given us (some of it on airfoils).
What would keep you from going to an airfield with a tape measure and an inclinometer to take some measurements. Surely these measurements could be translated into formulae to make an airfoil model.
Pair up in threes. - Yogi Berra
Just buy youself a copy of X-plane. Some airplane manufacturers use it when designing planes. I don't know if it would give you the data you want, but at least it would give you a very good idea of what would happen.
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I have encountered the same lack of current information and airfoil performance. I am a garage-engineer that produces experimental r/c aircraft somewhat regularly.
p ro files/NACA4.html
_ Gi nsberg/
I have found several gpl/shareware programs that do help design airfoils and predict their usability, but on a small scale for r/c. And the properties obviously change for real-world aircraft.
here are some links that may help though:
http://www.pagendarm.de/trapp/programming/java/
http://raphael.mit.edu/xfoil/
http://ourworld.compuserve.com/homepages/Harold
http://www.compufoil.com
http://www.profili2.com
http://www.ozemail.com.au/~malhardy/
These are applications that I have used with mixed success. And remember - most of these are for model aircraft so YMMV.
Also just google, there are lots of others out there who have run into the same situation and started the own projects to make data available.
Until I googled, I had no idea what an 'airfoil' was, the word isn't in my English dictionary here in England.
Turns out he's just asking about Aerofoils but it's one of those words that the Americans spell wrong, like 'color' and 'potatoe'.
I suggest he tries all the places he already looked, but use the spelling the rest of the world uses.
A pizza of radius z and thickness a has a volume of pi z z a
It is very interesting that you call yourself an Aero Eng student, but haven't mentioned anything about the NACA series of aerofoils (or maybe that is what you are calling 1960s or earlier). Why modern aerofoil data is required, as opposed to these foils is not known. If you are on the cutting edge of design, then you should have ready access to a wind tunnel for testing. If you don't, then you should be able to convince your instructors to let you carry out a project to derive appropriate NACA data for your modern aerofoil.
A standard NACA series aerofoil should suffice for your project, until everything else related to the design is settled to maximum efficiency (propulsion and so on). The six series aerofoil is actually the basis for the F-15 wing, it uses the 64A modified with camber at the leading edge. A lot of modern aerofoils are derived from the six-series NACA aerofoils, so they would make for a great starting point, while you modify the design to meet your requirements.
If you really must use a custom design, I would reccomend using X Plane and the aircraft design module, and design the aerofoil within that module. This also allows flying of the model in the simulator. X Plane uses Finite Element Analysis to carry out the appropriate computations to work out if the design will work, and generate lift in accordance with design principles.
Building your own wind tunnel / test rig would also be a possibility, such as the Wright brothers did, in order to test your designs. A good read of
Aircraft Design: A Conceptual Approach by Daniel P. Raymer;
Aerodynamics for Naval Aviators by the USN ASA-ANA ISBN 1-56027-140-X;
Modern Combat Aircraft Design by Klaus Huenecke also explains the F-16 wing as the NACA 64A204 series (modified) - although these last couple of titles would probably gain unwanted attention now-a-days.
I remember being able to develop a decent approximation for the E-2C Hawkeye and the Concorde aerofoils as part of my assignments at Uni. Surely your Uni / College library would have suitable titles on the shelves with some more in-depth listings of aerofoils and their application, and the appropriate modifications. The NACA series aerofoil data should also be available online (at least I remember that used to be the case).
Good luck with your project, anyway.
InfoSec that matters, when it counts.
The BBC's car review site has some erm, 'interesting' examples of amateur aerodynamic modifications:
e /0 /
http://www.topgear.com/content/fun_stuff/carbag
A pizza of radius z and thickness a has a volume of pi z z a
TetrUSS is a suite of computer programs used for fluid dynamics and aerodynamics analysis and design. The TetrUSS system was developed at NASA Langley Research Center during the 1990s to bring the state-of-the-art in computational fluid dynamics (CFD) to a higher level of utility, and is geared towards novices and experts alike.
Not sure if it is what you are looking for, but works both on PC and Mac OS X
http://aaac.larc.nasa.gov/tsab/tetruss/mac/
Who is the master of foxhounds, and who says the hunt has begun? -Pink Floyd
I don't know how much help this will be but it worth a shot. Try contacting R/C airplane manufacturers for specs on some R/C planes. Before you scoff this off as a flame. Remember that R/C flight is the same principle just a smaller scale. Many manufacturers also have modern aircraft on their production lists. One I am sure of is VioJet. Google search VioJet. If I remember correctly they make a F-16 that has an actual propane turbine. That produces some 24 lbs. of static thrust. Hows that for technology.
I am Bennett Haselton! I am Bennett Haselton!
Sure CFD doesn't use wind tunnel data to get performance characteristics, but the first principles approach used compairs very favorably to data that is available. Try Fluent or CFX if you can get your hands on them, they are pretty easy to use, esp for 2D sections...
Disclamer: I am a former CFD developer turned turbine airfoil designer at a major jet engine company, so I tend to be a bigger fan of CFD than most people...
That said, we depend on CFD very heavily, we often skip rigs, and go straight to test engines with new airfoil designs these days. The major gotcha to watch out for is that it can take a lot of experience to determine when to trust the CFD, particularly if seperated flow or transitional flows are significant effects on the solution...
"I'll have a Guinness, no wait, make that a Coors Light" -Grad student I work with, who shall remain anonymous...
As an employee of one of the companies that has substaintial amounts of airfoil data, I would feel very confidant telling him to keep dreaming if he was thinking of that...
"I'll have a Guinness, no wait, make that a Coors Light" -Grad student I work with, who shall remain anonymous...
C'mon, it was not meant to be taken seriously (and it does not deserve to be moderated Insightful ;-) ).
Paul B.
Dr. Mark Drela @ MIT is a great resource for these things. He is also an RC Sailplane enthusiast, so that is where I know him from. He is one of the most knowledgeable, helpful guys around, and makes all of his airfoils available to the public.
w w.monkeytumble.com/dnc/supergee.htm
http://raphael.mit.edu/DRELA.bio.html
http://w
thelocust[dot]org
Remember that big black bird that does Mach 3 at 80,000 ft (SR-71)? 1950's technology and still the fastest/highest jet ever. Granted, more modern data would be nice, but you can do a lot with 1960's aerospace tech.
It's too bad knowledge has been replaced with secrets. Think what we could do if everyone shared the knowledge. Instead we obsess about hiding our little sliver of information from the rest of the world and charging as much as anyone will pay to have a peek at it (after they sign a NDA of course).
-=-=-=-=- osjedi uses Debian GNU/Linux. -=-=-=-=-
You get yourself 120 laser pointers...
What is airfoil and does it protect against the government's mind reading rays?
Like others have said consistency is very important. When I go to Dunkin Donuts I know what I'm going to get. (although the service sucks) Customer Service is just as important. Experience what the customer experiences! Call your own phones to see how you are treated... Order your own products to experience the experience. This will tell you how your customer feels. I can't count the times I've had rude or unhelpful customer service reps.
Good luck...
Xfoil is good and airfoil data and geometry is easily gotten from nasg.com. You'll probably want to look at it in English. Abbot and Von Doenhoff is pretty useful, too. --Fellow ASE student
actually, that should be modded up. Unlike the parent poster, this guy (who jokingly called his link goatse) linked to the correct "xplane" site relevant to airplanes. The previous guy posted to some other corporate spam.