映射网格在缺口件多轴疲劳寿命预测中的应用

摘要

基于缺口件疲劳试验结果,采用ANSYS软件进行模拟计算,比较自由网格和映射网格对模拟结果的影响.模拟结果表明:在相近的单元数和节点数下,映射网格的计算时间仅为自由网格计算时间的一半;两种网格形式模拟得到的缺口根部应力值相近.将等效应变值作为损伤参量进行疲劳寿命预测,3个缺口半径下映射网格的预测结果均优于自由网格的预测结果;自由网格对于缺口半径为0.09 mm的损伤参量预测结果偏高程度达3倍,但随着缺口半径的增加,两种网格预测结果的精度均有所提高.%ANSYS software was employed to simulate the material elastic-plastic behavior based on the previous test results under multiaxial loading.The simulations are discussed between the free mesh and mapping mesh.It shows that the calculation time of mapping mesh is 50 % of that of free mesh when there is less difference in element number and node number between the two types of meshes.The stresses at the notched root from two meshes are almost the same.The fatigue life is predicted considering the e-quivalent strain as the damage parameter.The predictions of mapping mesh are better than those of free mesh.The damage parameter of the notched radius 0.09 mm is conservative 3 times for free mesh.The prediction accuracies of two meshes are improved with increasing notched radius.