轿车车身强度及刚度有限元分析

摘要

The strength and stiffness of the car body and frame were analyzed with finite element in order to modify and adjust finite element model to improve its generating speed. Parameter curved surface moulding technology was applied and parameter variable technique adopted to realize the automatic mapped gridding analysis for the full car body. The thin shell unit and heavy shell element simulation were used to simulate the car body and frame to establish the finite element calculation model for an overall and frame plate and shell elements of car body skeleton. The use of the mapped gridding unit to calculate, analyze and optimize storage data makes the analysis and calculation speed faster, the accuracy higher and the results better on the car body and frame deformation and stress distribution analysis. Under the bending and twisting working conditions, the strength and stiffness of the car body was analyzed to calculate the deformation and stress of the largest position. Based on the greatest stress area, the improved plan was put forward, which reduces the maximum stress.%为了便于修改和调整轿车整车的有限元模型,提高有限元模型生成速度,对轿车车身和车架的强度和刚度进行有限元分析.应用参数化曲面造型技术、参数化变量技术实现整车的映射网格自动剖分,应用薄壳单元和厚壳单元模拟车身和车架,建立了全板壳单元轿车车身骨架有限元计算模型.采用映射网格单元来分析计算,优化处理存储数据,使得车身、车架变形和应力分布的分析计算速度更快、精度更高,并且获得更好的分析结果.在弯曲、扭转工况下对轿车车身进行强度、刚度分析,计算出变形和应力最大部位,并依据最大应力区,提出改进方案,降低了最大应力.