基于CFD的车辆地面效应研究

Research on Road Vehicle Ground Effect Based on CFD

运用CFD(计算流体力学)仿真计算方法,对车辆气动升力的重要影响因素"地面效应"进行了研究。构建简化的车辆钝体模型,对不同的车辆离地间隙和车辆尾部扩散器的上翘角度进行仿真计算,获得不同工况下的速度场和压力场分布。在考虑气动阻力的前提下,研究车辆离地间隙和扩散器上翘角度对气动升力的影响规律。研究表明汽车离地间隙存在一个一定小的值使得气动负升力达到最大;一定小角度的扩散器可改善整车的流场品质,降低气动阻力,并且同时可以减小气动升力系数。

As an important influence factor of aerodynamic lift based on CFD,＂Ground Effect＂was researched in this paper.this paper tries to construct a simplified vehicle bluff body model,and do simulating calculation for different vehicle ground clearance and upwarping angle of diffuser of tail of vehicle to obtain the velocity field and pressure field distribution under different condition,and study the the effect law of vehicle ground clearance and upwarping angle of diffuser of tail of vehicle for aerodynamic lift,under the premise of considering aerodynamic drag.Research has shown that there is a small value in vehicle ground clearance,which make the pneumatic negative lift achieve maximum;diffuser with certain small angle can improve the flow field quality of vehicle,reduce aerodynamic drag,and can simultaneously reduce aerodynamic lift coefficient.