基于负泊松比结构的汽车B柱结构耐撞性优化设计

Crashworthiness optimization design of automobile B-pillar structure based on negative Poisson′s ratio structure

为了提高汽车的侧面耐撞性,基于传统B柱基本结构,提出了一种填充负泊松比内芯的新型B柱结构.根据我国新车评价规程C-NCAP要求,建立基于新型B柱结构的整车侧面碰撞模型;采用最优拉丁超立方试验设计法采取样本点,建立B柱各评价指标与设计变量之间的响应面模型;在此基础上,以B柱侵入位移和侵入速度为优化目标,采用NSGA-Ⅱ优化算法对新型B柱结构进行多目标优化设计.结果表明:新型B柱结构使得整车侧面碰撞的侵入位移下降了7.44%,侵入速度下降了5.10%,两者都有明显降低,这显著改善了汽车的侧面耐撞性能.

To improve the side crashworthiness of automobile,based on the traditional B-pillar basic structure,a new B-pillar structure with negative Poisson′s ratio inner core was proposed.According to the requirements of C-NCAP,the side impact model was established based on the new B-pillar structure.Taking sample points by the optimal Latin hypercube test design method,the response surface model between each evaluation index and design variable of B-pillar was established.On this basis,the invasion displacement and the invasion speed of B-pillar were used as optimization objective,and the NSGA-Ⅱoptimization algorithm was adopted to improve the new B-pillar structure by the multi-objective optimization design.The results show that the new B-pillar structure can reduce the invasion displacement by 7.44%with decreased invasion speed by 5.10%,which illuminates that the side crashworthiness of vehicle is significantly improved.