白车身多学科轻量化优化设计应用

在白车身开发早期阶段引入结构轻量化思想,建立隐式全参数化白车身模型,通过多学科优化过程,找到白车身零件形状、尺寸、位置与厚度等各参数之间的最佳组合,以及满足系统各项性能要求的重量最优解,使白车身轻量化设计的潜能得到最大程度的发挥。根据白车身自身性能的特点对其分成不同的优化区域分别进行不同工况的优化,从而合理地安排设计变量和样本点数量,并对由试验设计得到的近似模型进行多学科的轻量化优化设计,有效地控制分析与优化时间,给车身设计提供指导。最终得到的白车身方案减重12 kg,减重率达到4.5%。同时利用方差分析方法,对各设计变量对性能的贡献量与主效应进行分析,掌握设计变量对刚度,模态、被动安全性能以及重量的影响规律。

BIW Architecture Multidisciplinary Light Weight Optimization Design

Light weight design is introduced in the early phase of a new car body in white(BIW) development.SFE-Concept implicit parametric BIW model is build.The shape,size,position and gauge of BIW parts are balanced and all performance satisfy design target through multidisciplinary optimization.So this process reduces BIW mass maximally.BIW is divided into different optimization regions according to its performance characteristic for controlling the number of design parameters and the design of experiment(DOE) samples.Approximation model is created through DOE.Analysis and optimization time are controlled through optimizing approximation model.Finally an BIW meeting multidisciplinary performance target is obtained,saves 12 kg and lightweight effect is 4.5%.The design parameters percent contribution and main effect plots are obtained through analysis of variance(ANOVA).The rules between design parameters and performances(mass,stiffness,vibration modes and passive safety) are evidence according to percent contribution and main effect plots.