Abstract
Growing concerns about the environmental impact of road vehicles will lead to a reduction in the aerodynamic drag of all passenger vehicles, Sport Utility Vehicle s (SUV s) and light trucks. The wind tunnel remains the tool of choice for the vehicle aerodynamicist, but it is important that the benefits obtained in the wind tunnel reflect improvements to the vehicle on the road. Coastdown measurements using a small SUV in various configurations, have been made to determine aerodynamic drag and these have been compared with wind tunnel data for the same vehicle. The repeatability of the coastdown technique and the effect of blockage correction on the wind tunnel measurements are examined.
A good correlation between wind tunnel and on-road aerodynamic drag data is established for the configurations tested.