基于子模型仿真技术的发动机主轴承座设计优化

Design optimization of engine main bearing wall based on submodel simulation technique

针对某车用发动机主轴承座在该车型台架耐久性试验中开裂失效的问题,基于AVL Excite的曲轴动力学载荷分析,采用Abaqus和FEMFAT软件创建高精度的主轴承座螺栓疲劳仿真计算模型,通过理论计算分析确定主轴承座螺栓根部开裂的主要原因是螺栓连接副刚度不满足设计要求。考虑设计限制和制造成本,采用增大主轴承盖刚度和增加螺栓长度2个方案进行优化,优化后的轴承座能通过各项验证,满足车型疲劳耐久试验。

As to the cracking failure of the main bearing seat of a vehicle engine in the bench durability test of the vehicle model,based on the crankshaft dynamic load analysis of AVL Excite,the high-precision fatigue simulation calculation model of main bearing seat bolt is built using Abaqus and FEMFAT software.By theoretical calculation and analysis,it is confirmed that the main reason for the root cracking of the main bearing seat bolt is that the stiffness of the bolt connection pair does not meet the design requirements.Considering the design limitation and manufacturing cost,two schemes of increasing the stiffness of main bearing cover and increasing the bolt length are used to optimize the main bearing seat.The optimized bearing seat can pass various verifications,and meet the fatigue and durability test of vehicle model.