Vehicle Aerodynamic Drag for Tire Shape Parameters Using Numerical Analysis

摘要

Numerical analysis has been performed to understand the effect of tires of various shapes mounted on electric vehicles on the aerodynamic drag of the vehicle. For this study, an electric vehicle produced by General Motors is selected as the baseline model, and the baseline tire is 649.4 mm in diameter and 216.5 mm in width with 4 rain grooves 10 mm wide and 7.5 mm deep. A commercial flow solver, ANSYS Fluent, is used for this study. The driving speed of the vehicle is 110 km/hr, and a rotating wall boundary condition is imposed on the tire surface to reflect the rotation of the tire, and the MRF boundary condition is used to reflect the rotation of the wheel. Three types of tire shape parameters such as tire departure angle at tire outboard point, tire corner radius of curvature, and tire bulge rate of side wall are considered and tire shape change is performed using the morphing technique built in ANSYS Fluent. It is found that these shape parameters have a sensitive effect on the increase or decrease of vehicle's aerodynamic drag coefficient.