基于子模型法的柴油机连杆有限元分析方法

Research of the finite element method on diesel connect rod analysis based on submodel

采用有限元法对某型发动机连杆进行结构强度分析,阐述了在有限元计算中需要考虑的连杆部件几何模型,载荷边界条件及其处理方法。对于高强度螺栓,分别采用简化模型和精细子模型法进行分析并对比计算结果,结果显示简化模型和子模型法计算得到的螺纹位置应力分布截然不同,精细子模型能更真实地反映连杆螺栓在工作状态下的应力分布情况。最后对连杆进行疲劳强度校核,得到连杆疲劳寿命结果。从结果可以看出,该连杆的疲劳寿命满足永久寿命要求。

By using the finite element method,an analysis of a connect rod was processed,the component of rod and the boundary conditions should be considered,the treatment methods focused on these were expatiated.By using a simple model and a refined model with submodel method,an analysis of high strength bolt was carried out separately.Comparing the different stress contour map results of the screw thread obtained from these analyses,it shows that the refined model with submodel method can describe the distribution of the bolt stress in working condition more accurately.Finally,the fatigue intensity of the connect rod was verified and the fatigue life of the rod was obtained.The result shows that the connect rod fatigue life fulfils the permanent life requirement.