轿车前保险杠碰撞性能多目标优化

摘要

In the case of the bumper impact,the maximum energy absorbed by the bumper crash can be reflected by the total pressure collapse.In this paper,a multi-objective optimization problem was formulated,which with maximizing the absorption energy of the bumper and the mass ratio,minimizing the maximum variable of the X direction and the initial velocity decay time as objectives.The thickness of bumper beam,the left strengthen plate,the right strengthen plate and the wall thickness of energy absorption block were as the design variables.The impact information of the bumper beam under different design variables can be obtained by using the finite element software LS-DYNA.The objective functions were constructed based on the response surface method.And the optimal variable values were found in each response surface respectively.The multi-objective optimization can be solved by using the ideal point method,meeting ultimately the design requirements of structure.%在汽车保险杠碰撞问题研究中,完全压溃可以反映出保险杠碰撞中吸收的最大能量.本文建立了碰撞过程中保险杠吸收能量最大化、质量比吸能最大化、X方向最大形变量最小化以及初速度衰减时间最小化的多目标优化问题.以保险杆横梁厚度,左右加强板厚度,吸能块内外壁厚为设计变量,利用有限元软件LS-DYNA软件得到不同设计变量的压溃信息,通过响应面法构造近似目标函数,在各自响应面上寻找最优值,并利用理想点法求解多目标优化问题的有效解,最终完成了轿车前保险杠的碰撞多目标优化设计.