基于灵敏度分析的轿车车身轻量化

Research on the lightweighting of automotive body based on sensitivity analysis

以某轿车为研究对象,建立车身有限元模型,对车身进行弯曲、扭转刚度和模态分析。根据车身各构件的灵敏度分析结果确定优化设计变量,在保证车身刚度和模态性能不降低的前提下,以车身总质量最小化为目标优化车身构件厚度,最终得到的车身总质量减轻了11.12kg,刚度和固有频率均有所提高,达到了轻量化目的。对优化后的车身进行耐撞安全性验证,吸能效果较优化前也有所改善。

Took an automotive body as research subiect, established the finite element model, analysed its bending, torsional stiffness and modal. Calculated each part sensitivity of stiffness and modal to determine the sensitive regions. On the premise of good stiffness and modal properties, set the total body mass as objective function to optimize the parts＇s thickness. Ultimately, the total body mass got reduced about 11.12kg, but the stiffness and modal were improved. Validated the crashworthiness perforrnance of optimized body, found that the safety and energy absorption effect all improved than before. So in this paper, the lightweight design was effective.