连杆小头—活塞销接触的三维有限元素法计算

3—Dimensional Finite Element Method for contact Problem of Connecting Rod and Piston Pin

由于连杆孔—活塞销接触边界及载荷分布形式的不易确定,给连杆的有限元计算带来了困难。通常平面问题处理法假设的余弦或均布载荷常与实际不符,而平面接触解法则把销—活塞销孔与销—连杆孔接触的空间问题简化到了一个平面内,唯有三维接触解法才是最合理的。应用广泛的“SAP5”程序没有求解一般接触问题的自然功能。本文介绍了作者应用该程序求解柴油机连杆—活塞销三维接触问题的处理法,为三维未定边界接触问题的求解提出了一种行之有效的途径,并扩大了SAP5程序的应用范围。应用这种做法对E390柴油机连杆—活塞销三维接触作了计算。对销—孔接触的实际状态,接触边界、接触力等问题进行了研究。与运用“平面弹性接触有限元程序”计算的结果比较,两者接触状态相近。采用平面接触模型时在销直接作用区应力计算有较大误差。

An original processing for solving the contact problem of connectingrod and piston pin using the universal 3—dimensional F.E.M.SAP5 computer program was introuduced and an effective way for solv—(?)ng 3—dimensional contact problems with uncertain boundary was found.In this way the contact problem of connecting rod and piston pinwas calculated for E390 enginc and the actual contact condition,contact boundary and contact forces and ctc.were investigatcd.Itwas found that the computation by F.E.M.program for plane contactproblems results in a considerable crror of stress in the contact area.