缸套变形与活塞环适应性对环组漏气及摩擦学性能的影响

Effects of Cylinder Liner Deformation and Piston Ring Conformability on the Blowby and Tribological Performance of Piston Ring Pack

建立活塞环组-缸套系统的混合润滑仿真模型,模型中考虑活塞环组的热变形、缸套的热变形以及装配变形对活塞环-缸套系统摩擦学性能的影响,并通过模型分析缸套、活塞环变形以及活塞环适应性对漏气面积、环间压力、最小油膜厚度、摩擦力和磨损的影响。结果表明:变形对一、二环的漏气面积和一环与二环间的气体压力影响较大;考虑变形后,一环的摩擦力增大,二环的摩擦力减小,并且可以看到,在周向和轴向方向上一、二环环面的磨损是不均匀的;由于油环的适应性较好,变形对油环的漏气量及摩擦学性能影响较小。

A mixed lubrication model of the piston rings and cylinder liner system was developed, which considered the effects of the thermal deformation of the piston rings, the thermal and fitting deformation of the cylinder liner on the tribological performance of the piston rings and cylinder liner system.Meanwhile ,the effects of the profile deformation of cylinder liner and piston ring and the eonformability of piston ring on the ring leakage area, inter-ring pressures, minimum oil thickness, frictional force and wear were taken into account.The results show that the deformation greatly affects the leakage area of top and second compression ring and the pressure between top and second compression ring.Considering the deformation, the frictional force of top compression ring is increased while the frictional force of second compression ring is decreased.It is found that the wear of top and second compression ring is uneven in circumferential and axial directions.Due to the good conformability of oil control ring, the deformation hardly affects its blowby and tribological performance.