Effect of Wheel Housing Filling Ratio on Aerodynamic Characteristics of Sedan

Abstract:

By using computational fluid dynamics(CFD), this paper studies the effect of rotating wheels with different filling ratios on the aerodynamic characteristics of wheel housings of a sedan. The results are compared with the existing experimental data. It is concluded that while the filling ratio drops by 27%, the total drag coefficient rises nearly by 20% and the lift coefficient drops almost by 30%. The main reason for the drag coefficient reduction is the increased flow rate inside the wheel housings, which generates more flow separations, higher vorticity and lower car base pressure. The lower lift coefficient results from the accelerated flow near the underbody, which leads to lower local pressure.

Key words:vehicle aerodynamics; rotating wheel; wheel housing; filling ratio