Abstract:Under the excitations of combustion shock and piston slap,the dynamic deformation of cylinder liner is close to the surface roughness magnitudes,this may affect the friction and lubrication performance between piston rings and cylinder assemblies.To investigate the potential influences of structural deformations on tribological behaviours of cylinder assemblies,the dynamic deformation of the inner surface of cylinder liner was obtained by dynamic simulation,then introduced into the lubrication model after processing.The pressure stress factor and shear stress factor were calculated in real time using numerical integration to achieve more realistic simulation.An improved piston ringscylinder liner lubrication model was constructed by considering the effects of cylinder liner deformation and oil shear characteristics,the minimum oil film thickness and friction force curves were obtained by computation throughout the entire work cycle.The results indicate that the minimum oil film thickness and the friction force curves obtained from the improved model manifest some obvious fluctuations,and the friction force shows a significant reduction compared to the original model.