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On the Optimisation of Road Vehicle Leading Edge Radius in Varying Levels of Freestream Turbulence
Technical Paper
2006-01-1029
ISSN: 0148-7191, e-ISSN: 2688-3627
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English
Abstract
It has been recognised that the ideal flow conditions that exist in the modern automotive wind tunnel do not accurately simulate the environment experienced by vehicles on the road. This paper investigates the effect of varying one flow parameter, freestream turbulence, and a single shape parameter, leading edge radius, on aerodynamic drag. The tests were carried out at model scale in the Loughborough University Wind Tunnel, using a very simple 2-box shape, and in the MIRA Full Scale Wind Tunnel using the MIRA squareback Reference Car. Turbulence intensities up to 5% were generated by grids and had a strong effect on transcritical Reynolds number and Reynolds sensitivity at both model scale and full scale. There was a good correlation between the results in both tunnels.
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Citation
Newnham, P., Passmore, M., Howell, J., and Baxendale, A., "On the Optimisation of Road Vehicle Leading Edge Radius in Varying Levels of Freestream Turbulence," SAE Technical Paper 2006-01-1029, 2006, https://doi.org/10.4271/2006-01-1029.Also In
SAE 2006 Transactions Journal of Passenger Cars: Mechanical Systems
Number: V115-6; Published: 2007-03-30
Number: V115-6; Published: 2007-03-30
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