Optimization of the aerodynamic drag reduction of a passenger hatchback car

Abstract

An automatic optimization process is established employing computer-aided styling, computational fluid dynamics, grid deformation, an optimization method, and other digital simulation methods to reduce the computational time. Optimization was conducted for the aerodynamic shape of a hatchback car. Eight body design variables were selected after analysing the flow field. The first phase of body optimization was conducted for the front of the vehicle, the second phase for the rear of the vehicle, and the third phase for the global vehicle. Optimization reduced the front drag by 5.64%, then the rear drag by 7.21%, and finally the global drag by 10.34%, without changing the design style. There were interactions among those variables. The established process can be used in actual automotive styling.