基于离散伴随法与代理模型的整车气动阻力优化  

Optimization of Vehicle Aerodynamic Drag Based on Discrete Adjoint Method and Surrogate Model

作　　者：贺岩松[1] 曹礼鹏 张志飞[1] 李云 陈钊 He Yansong;Cao Lipeng;Zhang Zhifei;Li Yun;Chen Zhao(Shool of Automotive Engineering,Chongqing University,Chongqing 400030;Dongfeng Liuzhou Automobile Co.,Ltd.,Liuzhou 545005)

机构地区：[1]重庆大学汽车工程学院,重庆400030 [2]东风柳州汽车有限公司,柳州545005

出　　处：《汽车工程》2020年第11期1577-1584,共8页Automotive Engineering

基　　金：国家自然科学基金(51275540)资助。

摘　　要：本文中引入离散伴随法与代理模型,提出一种快速有效的汽车气动减阻优化策略。首先,通过对整车进行气动建模和仿真分析,得到风阻系数与测点压力的变化趋势,与风洞试验结果对比,二者吻合良好,表明模型精度满足要求;然后,以风阻系数为目标,采用离散伴随法对汽车表面进行灵敏度分析,进而确定前保险杠、后视镜、尾翼和后保险杠等灵敏度较高的部件作为优化对象;接着,以哈默斯雷试验设计法构建样本空间,利用网格自由变形技术参数化样本点模型并计算出与之对应的风阻系数;最后,采用Kriging插值法建立代理模型,选择多岛遗传算法对代理模型进行全局寻优。优化结果显示,整车风阻系数下降3.29%。The discrete adjoint method and the surrogate model are introduced to propose a fast and effective optimization strategy for reducing vehicle aerodynamic drag in this paper.Firstly,through the aerodynamic modelling and simulation analysis on vehicle,the changing tendency of drag coefficient and measured point pressure are obtained,which are then compared with the results of wind tunnel test.They agree well,showing that the accuracy of model meets requirements.Then with drag coefficient as objective,the discrete adjoint method is adopted to conduct sensitivity analysis on vehicle surface,and the components with higher sensitivity such as front bumper,rear-view mirror,tail wing and rear bumper are determined to be the objects of optimization.Next,the sample space is constructed by Hammersley design of experiment and the sample point model are parameterized by using mesh free form deformation technology with the corresponding drag coefficients calculated.Finally,the surrogate model is constructed by Kriging interpolation method,and the multi-island genetic algorithm is selected to perform a global optimization on surrogate model.The results of optimization indicate that the drag coefficient of vehicle reduces by 3.29%.

关 键 词：气动减阻 风洞试验 离散伴随法 网格自由变形 代理模型 

分 类 号：U46[机械工程—车辆工程]