This investigation was performed with the purpose of comparing the arodynamic drag of an automobile as measured in a full-scale wind tunnel with the drag as measured on the road. A definition of the drag coefficient as measured both on the road and in the wind tunnel is given in advance in order to allow a comparison to be made between the two operating conditions. Three medium size european cars were selected, one notch-back type and two hatch-back types. Road testing was mainly based on the coast-down method. The total resistance was determined by statistical analysis of the experimental results. The theoretical basis and the specifications of the procedure are investigated and justified. Additional outdoor and indoor tests were carried out in order to isolate the aerodynamic drag. The wind tunnel tests were conducted on the same cars fully equipped as tested on the road and in the same speed range. The wind tunnel tests being executed at steady speeds, however, supplementary road tests were performed in order to determine the effect of the deceleration on the aerodynamic drag. The final results show only small differences between the aerodynamic drag coefficients as measured in the wind tunnel and on the road with the procedure here described.
Automobile Aerodynamic Drag on the Road Compared With Wind Tunnel Tests
Sae Technical Papers
SAE International Congress and Exposition ; 1981
1981-02-01
Conference paper
English
Automobile Aerodynamic Drag on the Road Compared With Wind Tunnel Tests
Automotive engineering | 1981
|On-Road Aerodynamic Drag Measurements Compared with Wind Tunnel Data
British Library Conference Proceedings | 1995
|On-Road Aerodynamic Drag Measurements Compared with Wind Tunnel Data
SAE Technical Papers | 1995
|On-road aerodynamic drag measurements compared with wind tunnel data
Automotive engineering | 1995
|Wind Tunnel-to-Road Aerodynamic Drag Correlation
SAE Technical Papers | 1988
|