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Support Strut Interference Effects on Passenger and Racing Car Wind Tunnel Models
Technical Paper
2006-01-0565
ISSN: 0148-7191, e-ISSN: 2688-3627
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English
Abstract
In order to provide a correct aerodynamic simulation of a vehicle traveling along the ground, models are tested using rotating wheels in a wind tunnel with a moving ground. In the most common of configurations the model is supported by a vertical strut, usually designed as an aerofoil profile to minimize interference, with the wheels supported by lateral arms hinged to mounts outside the span of the moving ground plane. In using this type of configuration it is assumed that the presence of the intruding supports do not markedly affect the aerodynamic behavior of the model but this assumption is not always valid. In order to quantify interference effects from support struts, several models were tested over a stationary ground plane mounted to an under floor balance. Each model was tested with and without mock struts, which do not actually support the model. Comparisons were made between configurations with and without the mock struts in order to quantify their aerodynamic effects and investigate any changes in flow structure. Force and moment measurements show effects on both drag (up to 23 counts) and lift (up to 170 counts) due to a vertical overhead strut for all vehicle types. The overhead strut wake impinged on the rear wing of racing cars and the backlight of passenger vehicles as expected, but its influence was more wide ranging than this, extending to the vehicle under floor. Racing vehicles, whose performance relies greatly on the vehicles underside flow, are largely affected (up to 250 counts on lift and 26 counts on drag) by the presence of lateral wheel support stings. Passenger vehicles with larger ride heights were not sensitive to the use of lateral supports. Due to the complexity of support interactions, the effect of combined support methods was highly vehicle dependent, precluding the possibility of developing a reliable correction for interference effects.
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Citation
Hetherington, B. and Sims-Williams, D., "Support Strut Interference Effects on Passenger and Racing Car Wind Tunnel Models," SAE Technical Paper 2006-01-0565, 2006, https://doi.org/10.4271/2006-01-0565.Also In
References
- Borello, G. Beccio, S. Limone, S. Ferro, G. Bergamini, P. Quagliotti, F.B. The Role of the Moving Ground for Automotive Wind Tunnel Testing on Race Cars SAE Paper 1999-01-0647 , SAE World Congress, Detroit, Michigan March 1999
- Landman, D. Road Simulation for NASCAR Vehicles at the Langley Full-Scale Tunnel SAE Paper 2000-01-3550 , SAE Motorsports Engineering Conference, Dearborn, Michigan November 2000
- Arnette, S. Martinedale, B. Advances in Wind Tunnel Aerodynamics for Motorsport Testing SAE Paper 2000-01-03549, SAE Motorsports Engineering Conference, Dearborn, Michigan November 2000
- Borello, G. Beccio, S. Gollo, G. Quagliotti, F.B. Rolling Road Technology for Automotive High Speed Testing SAE Paper 2000-01-0353 , SAE 2000 World Congress, Detroit, Michigan March 2000
- Barlow, J.B. Rae, W.H. Pope, A Low Speed Wind Tunnel Testing John Wiley & Sons New York, NY 1999
- Hoerner, S.F. Fluid-Dynamic Drag 1965
- Davenport, W.J. Agarwal, N.K. Dewitz, M.B. Simpson, R.L. Poddar, K 1990 Effects of a Fillet on the Flow Past a Wing-Body Junction AIAA Journal 28 2017 2024
- Simpson, R.L. 2001 Junction Flows Annual Review of Fluid Mechanics 33 415 443
- Tamai, G The Leading Edge: Aerodynamic Design of Ultra Streamlined Land Vehicles Bentley Publishers Cambridge, MA 1999
- Fleming, J. Simpson, R.L. Davenport, W.J. 1991 An Experimental Study of a Turbulent Wing-Body Junction and Wake Flow Virginian Polytechnic Institute State University Blacksburg, Va
- Olcmen, M.S. Simpson, R.L. 1994 Influence of Wing Shapes on Surface Pressure Fluctuations at Wing-Body Junctions AIAA Journal 32 6 15
- Walter J.A. Patel, V.C. 1996 Measurements in Three-Dimensional Wake of a Surface-Mounted Winglike Symmetrical Ellipsoid Exp. Therm. Fluid Sci. 13 266 291
- Davenport, W.J. Dewitz, M.B. Agarwal, N.K. Simpson, R.L. 1992 Effects of a Leading-Edge Fillet on the Flow past an Appendage-Body Junction AIAA Journal 30 2177 2183
- LaFleur R.S. Langston, L.S. 1993 Drag Reduction of a Cylinder-Endwall Junction Using Ice Formation Journal of Fluids Engineering 115 26 32
- Moore, J. Forlini, T.J. “A Horseshoe Vortex in a Duct,” ASME Journal of Engineering for Gas Turbine and Power 106 1984 668 676
- Knowles, R Simulation and Experiments on an Isolated Racecar Wheel Rotating in Ground Contact 4th MIRA International Vehicle Aerodynamics Conference October 2002
- Page, M. Winkler, J. Roberts, N. Huschilt, T. Smyth, D. Kane, B. Recent Upgrades to the Swift 8ft × 9ft Rolling Road Wind Tunnel SAE Paper 02-MSEC-85 2002
- Eckerle, W.A. Langston, L.S. “Horseshoe Vortex Formation Around a Cylinder,” ASME Journal of Turbomachinery 109 1987 278 285
- Akehurst, A The Development of an Invisible Wind Tunnel Support Sting MEng Dissertation Durham University 2003
- Mercker, E. Wiedemann, J. Wickern, G. Aerodynamic Testing of Road Vehicles in Open Jet Wind Tunnels SAE SP-1465 1999
- Sims-Williams, DB Dominy, RG del Testing, SAE Paper 2002-01-3340 , SAE Motorsports Engineering Conference, Indianapolis, Indiana December 2002
- Sims-Williams, DB Dominy, RG The Design of a New Wind Tunnel for Vehicle Aerodynamics Research MIRA Vehicle Aerodynamics Conference Warwick, UK October 2002
- SensorTechnics Instruction Manual Signal Conditioned Precision Pressure Transducers series 103LP10D-PCB 1994
- Hetherington, B Williams, D.B. Wind Tunnel Model Support Strut Interference SAE Paper 2004-01-0806 , SAE World Congress Detroit Michigan March 2004
- Jenkins, L.N. An Experimental Investigation of the Flow over the Rear End of a Notchback Automobile Configuration SAE Paper 2000-01-0489 , SAE World Congress, Detroit Michigan March 2000
- Carr, G.W. Influence of Rear Body Shape on the Aerodynamic Characteristics of Saloon Cars 1974
- Hucho, W.H. Aerodynamics of Road Vehicles Society of Automotive Engineers Warrendale, PA 1998
- Nouzawa, T. Haruna, S. Hiasa, K. Nakamura, T. Sato, H. Analysis of the Wake Pattern for Reducing Aerodynamic Drag of Notchback SAE Models, 1990 Transactions – Journal of Passenger Cars Sec. 6 99 1990 486 494
- Maskell, E.C. Progress Towards a Method for the Measurement of the components of the Drag of a Wing of Finite Span Royal Aircraft January 1973
- Katz, J Dykstra, L. Effect of Wing/Body Interaction on the Aerodynamics of Two Generic Racing Cars SAE Paper 920349 , SAE Int. Congress, Detroit, Michigan February 1992