Finite Element Analysis Of The Diesel Engine Piston

As the main heated parts of a diesel engine,the piston withstand both the higher heatload, and under high gas pressure wich namely the mechanical load.Modern peopleconstantly improve the performance of the engine, and the country is also strictly to therequirement of environment pollution and energy consumption more and more,it is the onlyway of development to increase the power, rotation the speed and combustion condition ofthe diesel engine.Increasing power and rotational speed is bound to increase the heat loadand mechanical load of the diesel engine piston. therefore, whether the piston can worknormally under the high temperature and high load, has also become an important part toinfluence the diesel engine working.This article studies a piston of the IE6D275diesel engine.With the finite elementanalysis of it,concluded the temperature, stress and deformation distribution under the heatload, the mechanical load and both the thermal mechanical load effect,and analyze itsrationality, corresponding improving measures are put forward.The following is the maincontent of this paper:1. Establish the geometric model of the IE6D275type piston with PRO/E, and import themodel into the finite element software to carry on the grid, then simulate and calculate it,the boundary conditions of the temperature and the coefficient of heat transfer is simulatedin the working process of the internal combustion engine and calculated by empiricalformula, finally,we obtained the piston temperature field, the piston stress field and thepiston deformation distribution separately under the heat load. Use hot plug test method tomeasure temperature in different parts of the diesel engine piston, compared with thetemperature distribution of simulated calculation, we can verify the rationality of the pistonmodel built in this paper and the results of simulation calculation.2. Respectively, separated under the mechanical load,under thermal load and mechanicalload coupling, we simulate to calculate the temperature field, stress field distribution anddeformation distribution of the diesel engine piston.Compare with the piston distributiononly under the thermal load, only under the mechanical load and under the heat load andmechanical load coupling action, the results show that under the coupling action,thehighest temperature of the piston is not too muchu change, the maximum temperature is 375℃, the maximum stress value increases more, its value is254.8MPa, the biggestdeformation under the heat load of deformation is reduced, its value is0.342mm.3. By analyzing the temperature, stress and deformation distribution, it is concluded thatthe temperature and stress values under the coupling action are larger,beyond the allowablescope of the material, so we must put forward the corresponding improvement program.4. The two methods to improve the piston are the bottom spray cooling and cooling trough,analysis and compare the results with no cooling model, it can be seen from the results, acooling groove is better than use the bottom spray cooling measures. Simulation each of thedistribution under three kinds of cooling groove position of the piston,compared thedifferent influence of the results and selected model B for the optimal solution.Simulatingcalculation type B cooling tank, it is concluded that the highest temperature is309℃, themaximum stress value is156MPa, the maximum deformation is0.242mm, all the resultsis within the allowable range of the material, so choose the model B cooling tank for theoptimal way of improvement.