Comparative analysis of the aerodynamic behavior on Ahmed body mounted with different wheel configurations

Wheel configuration is the great significance for vehicle aerodynamics, and understanding the influences of wheel configuration on the aerodynamic behaviors of vehicle is a good choice to effectively decrease aerodynamic drag and optimize aerodynamic efficiency. In this study, the aerodynamic characteristics of Ahmed body mounted with different wheels configurations were evaluated by Computational Fluid Dynamics (CFD) using the lattice Boltzmann method. The simulation results were compared with published research data to study resolutions independence and verify the accuracy of the numerical method. The four opening areas of the rim were used to form different wheel configurations. The result showed that the drag of the front and rear wheels increases linearly with the increase of the rim opening area, while the drag of the bodywork decreases linearly. Downstream the body region, the structures of vortex shedding and surface pressure presented differences for each wheel configuration, which further resulted in different fluctuation intensities in wake vortices. The order of the width of the wake vortices in wheel region was as follows: W-4 > W3 > W2 > W1. The front wheel had a mainly affect on the time-averaged slipstream peak around the outside of vehicle body.