电动汽车底部流动分离对风阻的动态影响

doi:10.19562/j.chinasae.qcgc.2025.05.011

Abstract

Abstract:

In this paper， an electric vehicle's aerodynamic drag and wake are numerically studied. The results show that the flow separates from the rear of the car may roll up into a large-scale vortex at Re_L =1.1 $×$ 10⁷. The ratio of the RMS drag and the mean drag reaches to 3.27%， making an unneglectable effect on ride comfort and mileage prediction. The pressure at the back， the underbody， the middle and lower parts of the near wake， the aerodynamic resistance of the entire vehicle， the pressure near the wall of the rear guard plate in the bottom， and the separation flow at the bottom all have a characteristic frequency of 12 Hz. However， the flow separation at the top and C-pillar of the car does not have this characteristic frequency. It proves that the underbody flow separation at the rear is the main cause of dynamic changes of the aerodynamic drag.

Key words: electric vehicles, underbody flow, wake, aerodynamic drag

Qianwen Zhang,Lei Xu,Qingyang Wang,Shengjin Xu. Dynamic Effect of Underbody Flow Separation on Aerodynamic Drag in Electric Vehicles[J].Automotive Engineering, 2025, 47(5): 910-919.

Figures/Tables 16

References 17

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Dynamic Effect of Underbody Flow Separation on Aerodynamic Drag in Electric Vehicles

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