中文摘要：

目前活塞裙部润滑分析中一般认为活塞裙部-缸套摩擦副在一个内燃机工作循环所有行程中全部处于充分润滑状况,而实际中当活塞上行（向上止点运动）时,入口处的润滑油量不一定能保证该摩擦副处于充分润滑状况.结合活塞二阶运动模型、流体润滑模型和润滑油流动模型,计算活塞裙部向下（止点）运动后滞留在气缸套壁面上的润滑油量,并以此作为活塞上行期间活塞裙部-缸套摩擦副的润滑油进入量,进行活塞裙部-缸套摩擦副的润滑分析.结果表明,与以往认为所有行程中活塞裙部-缸套摩擦副全部处于充分润滑的分析比较,活塞裙部润滑分析中考虑实际润滑油输送确定活塞上行期间摩擦副的润滑状况时,活塞裙部-缸套摩擦副的润滑性能和活塞二阶运动等都有较明显的变化.

英文摘要：

In current lubrication analysis of piston skirt,the piston skirt-cylinder liner frictional pair is usually supposed to be lubricated sufficiently in all strokes of an operating cycle of intemal combustion engine.In fact,the status of sufficient lubrication of this frictional pair may not be guaranteed by the actual quantity of lubricating oil at entrance during the piston upstroke.Based on the model of piston secondary motion,the model of fluid lubrication and the model of lubricating oil flow,the quantity of lubricating oil stayed on the cylinder liner during the downward movement of piston skirt is calculated,and then the lubrication of piston skirt-cylinder liner frictional pair is analyzed under the condition that the quantity of lubricating oil stayed on the cylinder liner is taken as the entrance quantity of lubricating oil during the piston upstroke.The results show that compared with the current analysis in which the sufficient lubrication in all strokes is assumed,the lubrication performance of piston skirt-cylinder liner frictional pair and the piston secondary motion are changed obviously when the lubrication status of frictional pair during piston upstroke in the lubrication analysis of piston skirt is determined by the actual transport of lubricating oil.