This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
On the Application of Classical Wind Tunnel Corrections for Automotive Bodies
Technical Paper
2001-01-0633
ISSN: 0148-7191, e-ISSN: 2688-3627
Annotation ability available
Sector:
Event:
SAE 2001 World Congress
Language:
English
Abstract
The classical theory of wind tunnel corrections calculated from potential flow theory is revisited. In this context a flow model uniformly valid for all types of test sections is developed for the correction of drag in automotive wind tunnels. To define and size the singularities setting up the flow model only geometrical properties of the model and measured force coefficients will be used. To achieve a correct representation of the flow about a vehicle body a number of improvements to the classical approach are proposed. Based on the uniformly valid flow model, correction formulae for closed wall, open jet and slotted wall test sections are given. For the open jet and slotted wall case it is shown, that the presented formulae are still incomplete, whereas for the closed wall case the correction is ready to use. The correction approach is validated step by step by comparison with appropriate experimental data.
Possible benefit of the correction is not only the ability to correct for unwanted wall interference effects, but also an improved understanding of wind tunnel test section design items. This can be utilized for an optimized design for new tunnels as well as for improvements of existing facilities.
Recommended Content
Authors
Citation
Wickern, G., "On the Application of Classical Wind Tunnel Corrections for Automotive Bodies," SAE Technical Paper 2001-01-0633, 2001, https://doi.org/10.4271/2001-01-0633.Also In
SAE 2001 Transactions Journal of Passenger Cars - Mechanical Systems
Number: V110-6; Published: 2002-09-15
Number: V110-6; Published: 2002-09-15
References
- LOCK, C.N.H. The interference of a wind tunnel on a symmetrical body ARC, R.&M. 1275 1929
- GLAUERT, H. Wind tunnel interference on wings, bodies and airscrews ARC, R.&M. 1566 1933
- YOUNG, A. D. SQUIRE, H.B. Blockage correction in a closed rectangular tunnel ARC, R.&M. 1984 1945
- GARNER, H. C. Subsonic wind tunnel wall corrections AGARDograph 109 1966
- EWALD, B. Wind tunnel wall corrections AGARDograph 336 1998
- COOPER, K.R. Closed-test-section wind tunnel blockage corrections for road vehicles SAE SP-1176 Warrendale 1996
- MERCKER, E. WIEDEMANN, J. On the Correction of Interference Effects in Open Jet Wind Tunnel SAE Technical Paper 960671 Detroit 1996
- MASKELL, E. C. A theory of the blockage effects on bluff bodies and stalled wings in a closed wind tunnel ARC, R.&M. 3400 1965
- MERCKER, E. A blockage correction for automotive testing in a closed wind tunnel J. Wind Engineering and Industrial Aerodynamics 22 149 167 1985
- THOM, A. Blockage corrections in a closed high speed tunnel ARC, R.&M. 2033 1933
- HERRIOT, J.C. Blockage corrections for three-dimensional flow closed-throat wind tunnels with considerations of the effect of compressibility 1950
- HACKETT, J.E. Tunnel-induced gradients and their effect on drag AIAA Journal 12 2575 2581 1996
- HACKETT, J.E. WILSDEN, D.J. Estimation of wind tunnel blockage from wall pressure signatures: A review of recent work at Lockheed-Georgia AIAA Paper 78-828 1978
- Blockage corrections for bluff bodies in confined flows London 1980
- STRICKER, R. Möglichkeiten der Berechnung in der Kraftfahrzeugaerodynamik (Possibilities for numerical computation in vehicle aerodynamics) VDI-Berichte Nr. 444 1982
- SUMMA, J.M. MASKEW, B. Predicting automobile aerodynamic characteristics using an iterative viscous/potential flow technique SAE Technical Paper 830303 Detroit 1983
- MOKRY, M. TEMPLIN, J. T. A source panel method for the calculation of boundary interference on automobile models in solid and slotted walls and 3/ 4-open jet wind tunnels Canadian Aeronautics and Space Institute Aerodynamics Symposium Montreal 1985
- GARRY, K.P. WALLIS, S.B. COOPER, K.R. FEDIW, A. WILSDEN, D.J. The effect on aerodynamic drag of the longitudinal position of a road vehicle model in a wind tunnel test section SAE Technical Paper 940414 Detroit 1994
- SWAIN, L.M. On the turbulent wake behind a body of revolution Proc. Roy. Soc. A125 647 659 1929
- SCHLICHTING, H. Boundary layer theory 7th McGraw-Hill Book 1979
- REICHARDT, H. ERMSHAUS, R. Impuls- und Wärmeübertragung in turbulenten Windschatten hinter Rotationskörpern (Momentum and heat transfer in turbulent wakes behind axisymmetric bodies) Int. J. Heat Mass Transfer 5 251 265 1962
- TAYLOR, G.I. The force acting on a body in a curved and converging stream of fluid ARC, R.&M. 1166 1928
- MERCKER, E. WIEDEMANN, J. Betrachtungen über die Korrektur von Windkanalinterferenzen in offenen Meßstrecken (Reflections on the correction of wind tunnel interference in open jet test sections) 3. Stuttgarter Symposium Kraftfahrwesen und Verbrennungsmotoren Expert Verlag 1999
- HACKETT, J.E. Drag, lift and pitching moment increments due to wall constraint in a two-dimensional wind tunnel” 38th AerospaceSciences Meeting and Exhibit 10-13 January 2000 Reno 2000
- KUECHEMANN, D. VANDREY, F. Ueber den Einfluss der Duese auf Widerstandsmessungen im Freistrahl II (On the effect of the nozzle on the result of drag measurements, Part II) ZAMM 22 15 22 1942
- MERCKER, E. WICKERN, G. WIEDEMANN, J. Contemplation of nozzle blockage in open jet wind tunnel in view of different ‘q’ determination techniques SAE Technical Paper 970136 Detroit 1997
- SCHWARTEKOPP, B. Remarks on nozzle-blockage correction 4. ECARA Blockage Subgroup meeting Stuttgart 2000
- ECKERT, W. MUELLER, R. Influence of different wind tunnel test sections - open jet, slotted walls, solid walls - on aerodynamic test results of passenger cars and a racing car. Innovation and Reliability in Automotive Design and Testing Proceedings of the 3rd International Conference 3 Florence 1992
- EVERHARDT, J. GORADIA, S. Velocity profile similarity for viscous flow development along a longitudinally slotted wind-tunnel wall AIAA 15th Aerodynamic Testing Conference / A Collection of Technical Papers
- EVANS, J,Y.G. Corrections to velocity for wall constraint in any 10 × 7 rectangular subsonic wind tunnel ARC, R.&M. 2662 1949
- BARLOW, J.B. RAE, W.H. POPE, A. Low-Speed Wind Tunnel Testing John Wiley & Sons New York 1999
- SCHWARTEKOPP, B. Some remarks on solid-blockage 3. ECARA Blockage Subgroup meeting Stuttgart 2000
- SCHWARTEKOPP, B. DaimlerChrysler Wind Tunnel Data SAE Subcommittee No. 9 Meeting (Aerodynamic Testing of Road Vehicles in Open Jet Wind Tunnels) April 1997 Stuttgart 1997