Abstract:In order to study the each cylinder wear distribution on the using condition of the multi cylinder diesel engine,a simulation method for the wear of cylinder liner and piston ring for a 12150 type multi cylinder diesel engine was established and verified.Through the joint simulation calculation of the multi cylinder diesel engine,it is concluded that the thermodynamic parameters of cylinder liner and piston ring such as combustion temperature,combustion pressure,cylinder liner temperature and mild cooling water temperature,and he kinetic parameters such as the thickness of oil film and the load of micro convex body are significant difference from each cylinder,which leads to the uneven wear of each cylinder liner.The first cylinder has the most intense wear,following by the fifth,the fourth,the third,the second and the sixth cylinder.The maximum wear depth of the first cylinder is located at the corresponding position of the crankshaft angle of 9°,which is 51.22 μm after working at the rated operating point for 400 h.The maximum wear depth of the sixth cylinder is 39.37 μm,it is decreased by 23.14% compared with that of the first cylinder.Mainly due to the latest air intake and the existence of cooling dead zone,the combustion condition in the first cylinder is the worst,the wall surface temperature of the cylinder liner is high,the hardness is low,and the lubricating oil film is thin,which leads to the largest load of the micro convex body of the friction pair and the maximum wear depth.While the sixth cylinder is on the well conditions of the early air intake and the best cooling,and the wear depth of the sixth cylinder liner is relatively minimum from the comprehensive effect.Therefore,the wear depth of the main and side thrust surfaces at the top deadend point of the first cylinder liner could be determined as the basis for incylinder technical condition detection and wear calculation of the 12150 diesel engine.