【摘要】 利用八节点等参有限元,进行了活塞裙润滑和弹性变形的耦合求解。首先给出了混合润滑方程和活塞裙弹性变形方程,然后给出了求解这些方程的有限元求解步骤。计算结果表明:考虑活塞裙变形的油膜压力场峰值一般比不考虑活塞裙变形的油膜压力场峰值大;不同转角下的油膜压力场形状不同,有时呈现抛物线性,有时呈现马鞍型。同时,发现不同转角下活塞裙中部变形较大,在做功行程变形较为明显,变形区域也随着转角的变化有所不同,有时集中在流场中部,有时却集中在流场周向两边。结果也表明:考虑弹性活塞裙下,油薄膜承载力在吸气、压缩、做功行程有一定增加,而且在做功行程增加较为明显;摩擦力也有所增加,但增加不明显;在排气行程,油薄膜承载力和摩擦力会出现波动,承载力波动较大。更多还原

【Abstract】 By the eightnode isoparametric finite element method , the elastohydrodynamic lubrication of a piston skirt is investigated. Firstly, the mixedlubrication model and elastic deformation model for the piston skirt are presented. The eightnode isoparametric finite element procedure of solving these models are given. Take a combustion engine for example, the calculation results show that pressure peak values including deformation of piston are bigger, as compared with those excluding deformation of piston. And, configurations of pressure field experience different variations with crank angles, from parabolic to saddleshaped ones, when deformation of piston skirt considered or not. Also, the elastic deformation of in the middle of piston skirt is significant, especially at expansion stroke, whose range is variable at different crank angles, sometimes at both the circumference edges of flow filed, sometimes in the middle of that. It can be found that the values of load capacity increase significantly at intake, compress and work stoke, with fluctuating at exhaust stroke, while friction force vary slightly at all strokes, when deformation of piston skirt deformation is considered.The effect of coupling lubrication an de deformation of the piston skirt should be taken into account, when a piston skirt lubrication is studied.更多还原