| With the increasingly stringent of emission regulations, the power of the internal combustion engine continues to be strengthened, and the heat load of the cylinder increases. As the important parts of combustion chamber, piston and cylinder liner are easy to lead to scuffing of cylinder bore, heat crack and piston ring sticking for the heating effect from high temperature gas for a long time. Therefore, it is of great significance to know the piston, ring and cylinder liner’s hot surface, the integrated thermal stress and thermal deformation situation under heat load for improving the engine performance during internal combustion engine design. Chose a high pressure common rail diesel engine as the research object, Three dimensional finite element method was used to carry out the following specific research works:(1) The main heated components had been tested in temperature field. The piston and the chamber of cylinder head’s temperature had been tested by the method of hardness plug. The cylinder liners’inner wall temperature had been tested by using thermocouple measurement. At the same time, having measured the import and exports’temperature and flow rate of cooling jacket, which was used to been the boundary conditions of fluid-solid coupling calculation. Analyzed the temperature distribution and trends of the piston and cylinder liners’key area in calibration conditions. The error source of test was analyzed. The error of the hardness plug method was controlled in the rang of ±3℃, and the error of the thermocouple method was controlled in the rang of ±1.5℃.(2) Established fluid-solid coupling simulation model, including bolt, cylinder head, cylinder head gasket, engine body, cylinder liner, piston, piston ring, piston pin, and cooling water jacket. The gas side boundary was obtained by building and calculating one-dimensional combustion model by using AVL BOOST software. Through CFD calculation, the boundary condition of the cooling water side was obtained. With the whole machine coupling calculation, the finite element software could be used to transform the complex outer boundary of the piston-ring group-cylinder liner to the inner boundary, which made the simulation environment closer to the real environment.(3) The ANSYS Workbench 3D simulation platform was used to realize the co-simulation of fluid-solid-thermal. The temperature field, thermal stress, thermal deformation, and thermal flux density of the piston, ring and cylinder liner were obtained. The analysis results indicated that the piston throat temperature was the highest. It showed a decreasing trend from top to bottom. The maximum von Mises stress appeared at the top of the inner cavity. The maximum deformation appeared on the belt pulley side. The three piston rings’temperature and thermal stress decreased in proper order along downward. The order of deformation, from large to small, is the second gas ring, the first gas ring, the oil ring. The high temperature of cylinder liner distributed in the top, where the area didn’t contact with the cooling water. It declined firstly, and then reascended along the axial direction. The maximum stress of cylinder liner mainly concentrated in the upper. The maximum deformation distributed at the place, where there was the nearest to the both ends of the body. The first and the second cylinder’s temperature were in a symmetrical distribution with the third and the fourth cylinder.The calculating temperature values of the feature points in the piston crown and the cylinder liner wall were compared with the experimental data. And the errors were less than 10%.
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