某轿车外流场数值模拟与分析  

Numerical Simulation and Analysis of Outer Flow Fields for a Car

作　　者：安震[1] 李旭[1] 李居莉[1] 

机构地区：[1]山东理工大学交通与车辆工程学院,山东省淄博市55049

出　　处：《农业装备与车辆工程》2012年第12期48-52,共5页Agricultural Equipment & Vehicle Engineering

摘　　要：汽车空气动力学特性对汽车的动力性、经济性和操纵稳定性起着举足轻重的作用。首先利用UG软件对某款轿车进行了建模,然后利用Fluent软件对该轿车车身模型的外流场进行了数值模拟,得到了速度矢量图、压力云图等计算结果,分析了其车身外流场的基本特点;最后根据车身结构要求及尺寸范围,确定了前风窗角度、后风窗角度、前部翘角、尾部翘角等4个对风阻系数Cd值影响较大的参数,在此基础上进行正交试验得出了9种不同的参数模型,以Cd值为评价依据,寻找一组最佳参数值,再以此组参数值建立车身模型,在同样条件下对其进行外流场模拟并与原模型对比分析,验证了优化后车身模型的正确性。Automotive aerodynamics characteristics play a decisive role on automobile＇s power performance, economy and stability. First UG software is used on a car for modeling, and then numerical simulation is carried out on the car body model and flow field with the Fluent software, the velocity vectors, pressure cloud calculation results are obtained, and the external flow field characteristics of the car body are analyzed. Finally, according to automobile body structure and size range, four parameters that have great influence on drag coefficient Cd value are identified, such as front windshield angle, rear windshield angle, front rake angle, rear rake angle. On the basis of orthogonal experiment with nine different parameters of the model, with Cd values as evaluation basis, a set of optimal parameter values are found and the model of vehicle body on this group of parameter values is established. Under the same conditions, the outflow field is simulated and compared with the former model analysis, the correctness of the body model after optimization is verified.

关 键 词：轿车车身 汽车空气动力学 汽车外流场分析 风阻系数 正交试验 

分 类 号：U270.1[机械工程—车辆工程]