轿车外流场的数值仿真与分析
Numerical Simulation and Analysis of External Flow Field of a Car

以一款轿车为算例，介绍了计算汽车外流场的模拟原理和步骤。采用RNG k-ε和大涡模拟（LES）相结合的计算方法，运用CFD软件FLUENT对三个速度下轿车车身外流场进行数值仿真模拟；计算结果反映了汽车外流场的气动特性，较好地模拟了车身表面分离流的运动情况；找到涡流运动相对剧烈的部位。
Taking a car for example, we presented the simulation principle and calculation steps of its external flow field. With both the RNG k-epsilon and the large eddy simulation (LES) method,the numerical simulation of the external flow field of the car body under three different speeds was conducted with the FLUENT, a CFD software. The calculation results indeed reflect the aerodynamic characteristics of the external flow field of the car, and the separated flow movement on the car body surface is better simulated. In addition, the positions where the vortex motion is relatively severe are also found