白车身接附点动刚度优化设计

摘要

白车身接附点动刚度性能对整车NVH有较大影响,通过对关键点进行动刚度分析,可以为车辆NVH性能改进提供理论参考,同时有利于缩短开发周期及降低开发成本.以某款车型为研究对象,阐述了详细工程设计阶段白车身接附点动刚度分析的基本原理、分析方法及评价标准,建立白车身有限元模型,利用NASTRAN进行模态频率响应分析,并结合该车型动刚度计算结果对相对薄弱点进行结构优化设计.通过动刚度锤击试验与CAE分析结果进行对比,验证了后者的准确性,从最大程度上保证了该车中低频NVH性能.%The dynamic stiffness of BIW attaching points has a large effect on vehicle's NVH performance.According to dynamic stiffness analysis of critical points,it can provide some theoretical reference to the vehicle's NVH performance improvement,which contributes to shortening development cycle and cutting R&D expenditure.This paper expounds the fundamental principle,analysis methods and evaluation criterion of BIW attaching point dynamic stiffness analysis in engineering design phase,and makes modal frequency response analysis by NASTRAN,and carries out optimization design focusing on some weak points based on dynamic stiffness calculation resuh of this car model.According to the contrast with dynamic stiffness hammer test and CAE analysis,it well validates CAE analysis results,thus ensuring NVH performance for low and middle frequency to the maximum.