Aerodynamic design optimization in rear end of a hatchback passenger vehicle 2019-01-1430
Aerodynamic evaluation plays an important role in the new vehicle development process to reduce the consumption of fuel and emissions and improve aero acoustics and thermal performance. Computational Fluid Dynamics (CFD) is extensively utilized to evaluate the performance of the vehicle at early design stage to reduce cost of proto-parts making and to avoid late design changes.
CFD is used to optimize the vehicle’s shape, profiles and design features from the very concept stage to improve the vehicle’s aerodynamic performance. Since the shape of the vehicle determines the flow behavior around it, hence performance is different for hatchback, notchback and SUV type of vehicles. In a hatchback vehicle, the roof line is abruptly truncated at the end, which causes flow separation and increase in drag.
In this paper, the effect of shape of a hatchback vehicle on aerodynamics at the rear end is studied along with drag reduction features like roof end extension, edges on c-pillar, rear combination lamp and rear bumper. Response surface method (RSM) is used to explore the sensitivity of various design parameters. Remarkable improvements in drag coefficient were achieved by changing the rear end design.
Keywords: Aerodynamics, Drag, FE, RSM, CFD