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Simulation Considerations for Commercial Vehicles in Strong Crosswind Conditions
ISSN: 0148-7191, e-ISSN: 2688-3627
Published September 30, 2014 by SAE International in United States
Annotation ability available
Aerodynamic testing of heavy commercial vehicles is of increasing interest as demands for dramatically improved fuel economy take hold. Various challenges which compromise the fidelity of wind tunnel simulations must be overcome in order for the full potential of sophisticated aerodynamic treatments to be realized; three are addressed herein. First, a limited number of wind tunnels are available for testing of this class of vehicle at large scales. The authors suggest that facilities developed for large or full-scale testing of race cars may be an important resource. Second, ground simulation in wind tunnels has led to the development of Moving Ground Plane (MGP, aka Rolling Road (RR)) systems of various types. Questions arise as to the behavior of MGP/RR systems with vehicles at large yaw angles. It can actually be deduced that complete simulation of crosswind conditions on an open road in a wind tunnel may be impractical. This is due to the fact that the atmospheric crosswind develops a deep boundary layer profile, such that the resultant inflow seen by the moving vehicle is effectively curved. Finally, prevailing methods of boundary corrections for automotive testing have focused largely on drag, with reasonably symmetric flow fields. Relatively long vehicles at large yaw angles develop highly asymmetric flow fields, so more complex boundary correction methods need to be developed. Although computational simulation of real-world conditions (i.e. with crosswind) may seem to be a little easier, various options need to be carefully explored for best results.
CitationBritcher, C., Mokhtar, W., and Way, S., "Simulation Considerations for Commercial Vehicles in Strong Crosswind Conditions," SAE Technical Paper 2014-01-2452, 2014, https://doi.org/10.4271/2014-01-2452.
- Flay, R.G.J.: “A Twisted Flow Wind Tunnel for Testing Yacht Sails”, Journal of Wind Engineering and Industrial Aerodynamics, 1996, 63(1-3), pp:171-182.
- Leuschen, J., “The Effects of Ground Simulation on Tractor-Trailer Combinations,” SAE Int. J. Commer. Veh. 6(2):510-521, 2013, doi:10.4271/2013-01-2454.
- Salari, K.: “DOEs Efforts to Reduce Truck Aerodynamic Drag through Joint Experiments and Computations”. DOE Annual Merit Review, May 14-18, 2012.
- Patten, J, McAuliffe, B.; Mayda, W.; Tanguay, B.: “Review of Aerodynamic Drag Reduction Devices for Heavy Trucks and Buses”. NRC-CNRC Technical Report CSTT-HVC-TR-205, May 2012.
- Walter, J., Bordner, J., Nelson, B., and Boram, A., “The Windshear Rolling Road Wind Tunnel,” SAE Int. J. Passeng. Cars - Mech. Syst. 5(1):289-303, 2012, doi:10.4271/2012-01-0300.
- Elfstrom, G.; “Trends in Aero-Acoustic Wind Tunnel Testing”, Canadian Acoustics, Volume 37, No.3, 2009.
- Hackett, J.E.: Recent Developments in the Calculation of Low-Speed Solid-Walled Wind Tunnel Wall Interference in Tests on Large Models. Progress in Aerospace Sciences, 39 (2003) pp.537-583
- Chen, M., Mokhtar, W., Britcher, C., and McGarry, J., “Experimental and Computational Aspects of Ground Simulation for Vehicles in Strong Crosswind Conditions,” SAE Technical Paper 2014-01-0588, 2014, doi:10.4271/2014-01-0588.
- SAE Recommended Practice “Wind Tunnel Test Procedure for Trucks and Buses”. SAE Standard J1252, Rev. July 1981.
- Chen, Mau-Kuo: “Use of a Rolling Road System in Crosswind Conditions”. PhD Dissertation, Old Dominion University, August 2013.
- Surface Vehicle Information Report “Aerodynamic Testing of Road Vehicles - Open Throat Wind Tunnel Adjustment”, SAE Standard J2071, Rev. JUN 1994.
- Mokhtar, W., Pervez, N.; “Underbody Drag for Pickup Trucks”, 30th AIAA Applied Aerodynamics Conference, New Orleans, LA, AIAA 2012-2231, June 2012.