轿车大客车会车时的气动特性

Transient Aerodynamics of Sedan and Coach Crossing Each Other

摘要:

应用CFD数值模拟方法，采用滑动交界面和动网格技术，对开阔路面下轿车大客车会车过程的瞬态流动进行气动特性研究。车辆模型采用MIRA典型阶背式轿车全尺寸模型和进行过风洞试验的国产JT6120型大客车简化模型。通过对会车过程流场的分析和对模拟结果的统计处理，获知了轿车大客车会车前后气动力系数变化趋势以及产生该变化的原因，得到了轿车大客车会车过程中定量的气动力变化规律。结果表明：轿车大客车会车过程气动力系数有很大变化，其中轿车的更大一些；两车气动力系数随时间的变化趋势有差异；会车状态的空气动力学作用对汽车操纵稳定性有重要影响。

Abstract:

Based on Computational fluid dynamics, the problem on transient aerodynamic characteristics of sedan and coach crossing each other on road is researched by adopting technology of sliding interface and moving mesh. The car model is MIRA which has been used for many years in foreign country and the coach model was JT6120 which has been tested many times in domestic wind tunnel. The trends and reasons of aerodynamic coefficients changing were obtained from the flow field of simulation results. The quantificational changing of sedan and coach aerodynamic coefficients when they cross each other was obtained. The simulation results indicated that the all aerodynamic coefficients of two vehicles changed large, and the sedan changed much more enormously than the coach. It is different between the trends of sedan and coach aerodynamic coefficients changing. The aerodynamic force was important to the vehicles’ handling stability when they crossing each other.