UIUC Low-Speed Airfoil Tests
The goals of the UIUC Low-Speed Airfoil Tests (UIUC LSATs) program are to design, analyze and wind tunnel test airfoils for low Reynolds number applications. The UIUC Applied Aerodynamics group has been a leader in this research area with new airfoil designs being applied to unmanned aerial vehicles, small wind turbines, model aircraft and many other applications. Over 200 low Reynolds number airfoils, many of them new designs, have been built and validated in the UIUC Subsonic Aerodynamics Lab 3x4 ft wind tunnel with the results being documented in books, reports, and journal/conference publications. The wind tunnel test data is available online and the books are available in print (see below). We maintain answers to our frequently asked questions here: LSATs FAQ.
Summary of Low-Speed Airfoil Data Books
Our data has been published in the series of volumes listed below:
Selig, M.S., Guglielmo, J.J., Broeren, A.P., and Giguère, P., Summary of Low-Speed Airfoil Data, Vol. 1, SoarTech Publications, Virginia Beach, VA, 1995, 292 pages. Wind tunnel data on 34 airfoils tested at Reynolds Numbers ranging from 30,000 to 500,000. [Book available here]
Selig, M.S., Lyon, C.A., Giguère, P., Ninham, C.N., and Guglielmo, J.J., Summary of Low-Speed Airfoil Data, Vol. 2, SoarTech Publications, Virginia Beach, VA, 1996, 252 pages. Wind tunnel data on 25 airfoils tested at Reynolds Numbers ranging from 40,000 to 400,000.[Book available here]
Lyon, C.A., Broeren, A.P., Giguère, P., Gopalarathnam, A., and Selig, M.S., Summary of Low-Speed Airfoil Data, Vol. 3, SoarTech Publications, Virginia Beach, VA, 1998, 418 pages. Wind tunnel data on 37 airfoils tested at Reynolds Numbers ranging from 60,000 to 500,000. [Book available here]
Selig, M.S. and McGranahan, B.D., Wind Tunnel Aerodynamic Tests of Six Airfoils for Use on Small Wind Turbines, National Renewable Energy Laboratory, NREL/SR-500-34515, Oct 2004, 133 pages. Also to appear as Summary of Low-Speed Airfoil Data, Vol. 4. Six airfoils tested at Reynolds Numbers ranging from 100,000 to 500,000.
[NREL report download]Related LSATs Book Links
- Composite plots of airfoils tested
- Alphabetical listing of all airfoils tested
- Listing of available datasets in tabular form: [ Vol 1 | Vol 2 | Vol 3 | Vol 4 ]
- Our airfoil data books may be purchased from SoarTech Aero Publications
Low Reynolds Number Airfoil Data and Documentation
- All of the low Reynolds number airfoil data in Vols 1-4 is available online in plain ASCII text files. The first two volumes include lift and drag coefficient data while
the second two volumes also include pitching moment data. - Our tests are supported in large part by a group of dedicated model makers / volunteers focused on a common interest in model aviation. If you are interested in helping and want to make a wind tunnel model for testing at UIUC, see the wind tunnel model construction notes for more information. For flapped models, brackets are added to the ends to secure the flap for specific settings. If you have in interest in a particular airfoil that you'd like to see tested, contact us.
S1223 lift and pitching moment plots: The S1223 is a popular airfoil used in the SAE Aero Design Competition. The airfoil first appeared in UIUC LSATs Vol 1 without pitching moment data, but these data were taken after Vol 1 and posted here online.
- Our airfoil data books may be purchased from SoarTech Aero Publications. Also available from SoarTech Aero Publications is the book Airfoils at Low Speed (aka SoarTech 8), which includes wind tunnel data on 54 airfoils tested at Reynolds numbers ranging from 60,000 to 300,000. The book contains extensive commentary and analysis. Testing was performed at Princeton University during 1987 and 1988 by Michael Selig, John Donovan and David Fraser.
Low Reynolds number airfoils are defined by having a laminar separation bubble that causes an increase in drag. This bubble can be seen by injecting smoke into the boundary layer and also by a technique called oil flow visualization [graphics downloads].
Low Reynolds Number Airfoil Publications
In addition to Vols 1-4, some low Reynolds number airfoil publications from our group are listed below.
- Selig, M.S. and McGranahan, B.D., "Wind Tunnel Aerodynamic Tests of Six Airfoils for Use on Small Wind Turbines," ASME Journal of Solar Energy Engineering, Vol. 126, November 2004, pp. 986-1001.
- Selig, M.S., "Low Reynolds Number Airfoil Design," VKI Lecture Series - Low Reynolds Number Aerodynamics on Aircraft Including Applications in Emerging UAV Technology, von Karman Institute for Fluid Dynamics (VKI) Lecture Series, RTO/AVT-VKI-104, November 2003.
- McGranahan, B.D. and Selig, M.S., "Surface Oil Flow Measurements on Several Airfoils at Low Reynolds Numbers," AIAA 42nd Applied Aerodynamics Conference, AIAA Paper 2003-4067, Orlando, FL, June 2003.
- Gopalarathnam, A., Broughton, B.A., McGranahan, B.D., and Selig, M.S., "Design of Low Reynolds Number Airfoils with Trips," Journal of Aircraft, Vol. 40, No. 4, 2003, pp. 768-775.
- Giguère, P. and Selig, M.S., "New Airfoils for Small Horizontal Axis Wind Turbines," ASME Journal of Solar Energy Engineering, Vol. 120, May 1998, pp. 108-114.
- Selig, M.S. and Guglielmo, J.J., "High-Lift Low Reynolds Number Airfoil Design," Journal of Aircraft, Vol. 34, No. 1, January-February 1997, pp. 72-79.
LSATs Archives
Some of our early newsletters/info and how we started is below. This stuff is old: