Aerodynamic Design Optimization in Rear End of a Hatchback Passenger Vehicle
Published March 25, 2019 by SAE International in United States
Annotation of this paper is available
Aerodynamic evaluation plays an important role in the new vehicle development process to meet the ever increasing demand of Fuel Economy (FE), superior aero acoustics and thermal performance. Computational Fluid Dynamics (CFD) is extensively used to evaluate the performance of the vehicle at early design stage to overcome cost of proto-parts, late design changes and for time line adherence.
CFD is extensively used to optimize the vehicle’s shape, profiles and design features starting from the concept stage to improve the vehicle’s aerodynamic performance. Since the shape of the vehicle determines the flow behavior around it, the 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 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 improvement in the drag coefficient was achieved by changes in the rear end design.
CitationBajpai, D. and Regin, F., "Aerodynamic Design Optimization in Rear End of a Hatchback Passenger Vehicle," SAE Technical Paper 2019-01-1430, 2019, https://doi.org/10.4271/2019-01-1430.
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