基于瞬态响应的SUV后背门开闭疲劳有限元分析及优化设计

为解决某SUV车型后背门在开闭耐久性能试验中焊点开裂问题,建立了一种基于瞬态响应分析的后背门开闭疲劳有限元分析方法.依据后背门开闭耐久性能试验规范,确定有限元分析中的输入载荷、约束条件、运动关系和接触关系等.运用ABAQUS对后背门进行瞬态响应分析,得到后背门在关闭过程中的瞬态应力时间历程.运用雨流计数法得到一系列横幅...

Slam Fatigue Finite Element Analysis and Optimization of SUV Liftgate Based on Transient Response Analysis

In order to solve the spot welds crack problem of the liftgate of an SUV in the slam durability test,and a finite element analysis method of the slam fatigue of the liftgate was established based on the transient response analysis.The input load,constraint condition,kinematic relation and contact relation of the finite element analysis were determined according to the test specification of the slam durability performance of the liftgate.ABAQUS was used to analyze the transient response of the liftgate,and the transient stress time history of the liftgate during closing was obtained.Using the rain-flow counting method,a series of stress cycles of banners were obtained,based on the S-N curve of the spot welds and the Miner linear fatigue damage accumulation theory,fatigue damage was calculated using FEMFAT.The results show that the damage of two spot welds cracked in the slam durability test is over the target value.By analyzing the force transferring path of the original scheme,the optimized scheme was obtained and fatigue analysis was carried out.The results show that the fatigue damage value of each spot welds in the optimized scheme is less than the target value,and it passes the subsequent slam durability test.There is a good correlation between the finite element analysis results of the liftgate slam fatigue based on the transient response analysis and slam durability test.