基于一维搜索的车身轻量化设计

Lightweight Design of BIW Based on One-Dimensional Search

以一款低速电动乘用车为研究对象,讨论了车身静态分析有限元模型的建立过程。提出了基于一维搜索的车身轻量化设计方法,以应力为约束条件,零件质量最小为目标函数,对车身结构进行轻量化优化设计。优化后车身零件的应力值都向屈服极限靠拢,实现材料的充分利用。最后通过对比采用全局优化方法和整体优化与局部厚度改进相结合的优化方法发现,采用整体优化与局部改进的设计方法对提高材料的利用率更有效。

A low-speed electrical passenger car was taken as the research object, and its finite element model for static analysis was established. A lightweight design method of BIW based on one-dimensional search was proposed. In the structure optimization mathematical model, the stress values of the parts were taken as constraint condition, the total mass minimization of all the parts was taken as objective function. After the optimization procedure, the stress values of parts were respectively close to their yield limits. The utilization ratios of materials were fully improved. Finally, through the comparison between global optimization algorithm and global optimization combined with local optimization, it can be found that global optimization combined with local optimization is more efficient in improving material utilization.