发动机连杆强度及稳定性分析

Analysis of Engine Connecting Rod Strength and Stability

针对新设计的发动机连杆,采用有限元仿真分析方法校核其强度及稳定性。通过对发动机连杆进行承载分析,并建立发动机连杆有限元模型,对发动机连杆及联接螺栓进行了强度分析,采用预应力模态分析方法对发动机连杆进行了模态分析,基于屈曲分析理论对发动机连杆进行了屈曲分析。分析结果表明:发动机连杆最大等效应力为500.28 MPa,安全系数为1.57,连杆联接螺栓最大等效应力为251.99 MPa,安全系数为2.54。证明了连杆及联接螺栓均满足强度设计要求;模态分析得到连杆与活塞联接处易发生振动失圆;发动机连杆一阶屈曲载荷系数为6.24,连杆的屈曲临界载荷为727 667.87 N,连杆设计满足屈曲稳定性要求。上述分析可为发动机连杆设计提供参考。

For the newly designed engine connecting rod,the strength and stability of the newly designed engine connecting rod are checked by finite element simulation analysis method.Through the bearing analysis of the engine connecting rod and the establishment of the finite element model of the engine connecting rod,the strength analysis of the engine connecting rod and the connecting bolt is carried out.The modal analysis of the engine connecting rod was carried out using the prestressed modal analysis method,and the buckling analysis of the engine connecting rod was carried out based on the buckling analysis theory.The analysis results show that the maximum equivalent stress of the connecting rod of the engine is 500.28 MPa,the safety factor is 1.57,the maximum equivalent stress of the connecting rod connecting bolt is 251.99 MPa,and the safety factor is 2.54.It is proved that the connecting rod and the connecting bolt meet the strength design requirements.The modal analysis shows that the connection between the connecting rod and the piston is prone to vibration out of circle.The first-order buckling load factor of the engine connecting rod is 6.24,and the critical buckling load of the connecting rod is 727667.87 N,the connecting rod design meets the requirements of buckling stability.The above analysis can provide a reference for the design of the engine connecting rod.