【摘要】 采用动力学仿真软件ADAMS和有限元分析软件ANSYS,辅以手工编程相结合的方法,研究计入轴瓦变形时某四缸柴油机曲轴动应力分析和疲劳强度计算问题。解决计入轴瓦变形的曲轴—轴承系统动力学和摩擦学分析问题,得到动态油膜压力;采用ANSYS中的参数化编程语言APDL编写程序实现动态施加力边界条件,计算曲轴动应力;采用损伤积累理论计算曲轴疲劳强度。研究表明:计入轴瓦变形,主轴承最小油膜厚度大幅度下降,最大油膜压力大幅度上升,曲轴动力学响应和危险点的动应力也发生变化,曲轴疲劳寿命下降了15.6%。更多还原

【Abstract】 Dynamic stress and fatigue strength of a crankshaft of diesel engine with four cylinders is studied with consideration of the elastic deformation of bush. Special software ADAMS and ANSYS, assisted by self-designed programs, are adopted to solve the problem. The dynamic pressures of oil film in the bearings are obtained by analysis of dynamics and tribology of the crankshaft-bearing system with consideration of bush deformation. Programming language APDL in ANSYS is adopted to compile program for realizing the force boundary condition, then the dynamic stress on crankshaft journal surfaces is calculated. The fatigue strength of crankshaft is calculated by using damage accumulation theory. It is shown that the minimum thickness of oil film decreases and the maximum pressure of oil film increases to a great extent if the elastic deformation of bush is taken into consideration. The dynamic response and stress of crankshaft vary and the fatigue life of crankshaft decreases by 15.6%.更多还原