关于改进Pareto遗传算法车身气动多目标优化.pdfVIP

学兔兔 汽 车 工 程 2014年(第36卷)第10期 Automotive Engineering 2014233 基于改进的Pareto遗传算法的车身气动多目标优化木 书 甘，杨志刚，李启良 (同济大学上海地面交通工具风洞中心，上海 201804) [摘要] 把气动性能和空间性能作为优化目标，用改进的Pareto遗传算法求解得到流线型车型和普通车型无 轮车身的Pareto波阵面。通过二维车身优化算例验证，以小家族为单位进行进化的邻点交叉法、分象限外推法和单 目标预测法配合使用，可以有效提高子代的分布性能和进化效果，解决三维车身气动优化中计算量过大的问题。流 线型车型与普通车型的Pareto波阵面相比，在中低阻区，前者的综合性能更优秀，在高阻区则反之。 关键词：Pareto最优解；遗传算法；气动优化；多目标优化 Multi—Objective Aerodynamic Optimization of Car Body Using Improved Pareto Genetic Algorithm Wei Gan．Yang ZhigangLi Qiliang Shanghai Automotive耳 Tunnel Center．Tong／i Unive~ity．Shanghai 201804 [Abstract] Improved Pareto genetic algorithm is used to conduct a simulation with the aerodynamic and spa· tial performances of car body as objectives，and the Pareto fronts of wheel-less car bodies with both conventional and streamline styling are obtained．A 2D car body optimization example verifies that the adoption of neighbouring-point crossing and quadrant allocation／extrapolation combined with single objective prediction can effectively enhance the distribution performance and evolution effects of offspring，and solve the problem of heavy computational efforts in 3 D car body aerodynamic optimization．In the comparison between the Pareto front of car body with streamline sty— ling and that with conventional styling，the former’S overall performance is better at low-and middle Cd region，and is just the opposite at high Cd region． Keywords：Pareto optimum；genetic algorithm；aerodynamic optimization；multi-objective optimiza- tion