The Thermal Load Simulation Analysis Of Piston, Cylinder And Cylinder Head Of Engine

The thermal load of parts is one of the main factors that restrict the further strengthening of engines, which directly affect the durability, reliability and economy of engines. Therefore it is an important problem to calculate the thermal load of parts of engines, to consider the factors that affect the thermal load and to take measures to reduce the thermal load when an engine will be designed.The Finite Element Analysis (FEA) is a mainly method for engine thermal load analysis, which is used to simulate thermal load of the piston, the cylinder and the cylinder head of a small aviation gasoline engine. In the process of thermal load simulation, models of piston, cylinder and cylinder head are designed and constructed by making use of Pro/Engineer according to the provided data and the knowledge of engine design, and imported into the finite element analysis software ANSYS to mesh. Boundary conditions are calculated according to empirical formulas and data from related researches and target parameters of the engine to be designed and then simulation analysis is carried out.The thermal load in take-off condition is compared and analyzed with that in maximum life condition. Simultaneously impacts on thermal loads of engine parts result from altitude, the average temperature of gas and the heat transfer coefficient are considered. In addition, the influence of cooling water on the thermal load of the cylinder head and the influence of injection cooling on the thermal load of the piston are discussed.Models of parts of the engine are modified, re-simulated and calculated because high-temperature regions and high-thermal stress regions are existed through the results of thermal load analysis on parts of the engine under a variety of factors. Finally rational methods of designing and improving the engine are proposed in this thesis.