The Study And Analysis Of Heat Transfer Simulation Of The Engine Exhaust Valve

Valve as a main element of vavle train mechanism of engine, it plays an important part to make sure that the engine can acquire enough economic performance, power performance, reliability and durability of an engine. But with the further strengthened structure or changed working condition of the engine, the vavle working environment becomes worse. And the failure of engine valve especially exhaust vavle becomes a serious problem.This paper describes some reasons and forms of losing efficacy of vavle.And it also shows some research methods and results of the losing efficacy of vavle. It shows that high temperature and thermal load are the main reasons of exhaust vavle's failure problem.This paper conducts a simulation of working process of the Q492 engine as an example with the Matlab analysis software. Through the simulation, indictor diagram and transient heat transfer coefficient are computed . It proposes a simulation method to compute heat transfer and deformation of the exhaust vavle.And with this method, it can predict the engine indictor diagram and describe the heat transfer situation of the exhaust valve as well as temperature distribution. So it can prevent losing efficacy of the exhaust vavle by choosing resonable related parameters. Meanwhile this article conducts heat transfer simulation and analysis of the exhaust vavle under different working conditions as well as with different conductivity values of the vavle material. It also analyzes the exhaust valve heat transfer situation used LPG gas as the fuel with the same speed and compression ratio.