Aerodynamic Performance Assessment of Multiple Car Body Configurations: A Comparative Study

This study presents a comparative computational fluid dynamics (CFD) investigation of the aerodynamic performance of four simplified crossover/sports utility vehicle (SUV)-type vehicle body configurations. The models were developed with systematic geometric variations, including front face inclination, roof spoiler length, roof spoiler slotting, and rear underbody diffuser integration. Steady-state Reynolds-averaged Navier–Stokes (RANS) simulations using the k–ω SST turbulence model were conducted in ANSYS Fluent to evaluate key aerodynamic parameters, including the drag coefficient, drag force, pressure distribution, velocity field, and modeled turbulence kinetic energy. The results indicate that the baseline configuration exhibits the highest drag due to early flow separation and poor rear pressure recovery. Progressive geometric modifications led to improved aerodynamic performance, with the configuration incorporating a slotted roof spoiler and rear diffuser achieving the lowest drag coefficient, corresponding to an approximate 13% reduction compared to the baseline model. The findings demonstrate that coordinated front- and rear-end design modifications play a critical role in reducing wake intensity and enhancing aerodynamic efficiency. This study provides insight into effective drag reduction strategies for crossover-type vehicles and highlights the importance of integrated aerodynamic design approaches.