轿车白车身试验模态与计算模态相关性分析

摘要

以某车型白车身为研究对象进行模态试验,确定了其模态参数.建立白车身有限元模型,计算了其自由模态.通过白车身模态试验结果和计算结果对比可知,二者相关性较差.对计算模型进行灵敏度分析,确定以车身钢板厚度为修改参数修改白车身模型,修改后模型计算结果与试验结果一致性较好,可作为后续NVH仿真分析的基础模型.%In this study, the modal test of a car BIW is performed and the modal parameters are obtained. The body's FEM model is established and the free mode is computed. It is concluded by comparing the computing results and the testing results that they have poor correlation. The sensitivity analysis of FEM model is made, and the thickness of body steel plate is chosen as design parameters to modify the BIW model, and the modified computing result agrees well with test result. The modified model can be used as the basic model of subsequent NVH simulation analysis.