发动机排气门传热特性有限元仿真分析
摘 要
气门是发动机配气机构的主要组成部件，它也是确保发动机获得足够经济性能、动力性能、可靠性及耐久性的重要零部件。但是随着发动机结构的进一步强化、运行工况的改变等原因，使得气门工作环境恶化，导致气门失效特别是排气门失效成为发动机日益显著的问题。
为解决发动机排气门的失效问题，本文对其失效原因、失效形式以及现阶段关于发动机排气门的研究方法与成果进行了重点分析,其中高温及高温负荷是造成排气门失效的最主要原因。故为防止发动机排气门失效，本文对其进行了传热特性分析，分析方法主要如下：通过传热理论分析计算确定发动机排气门传热基本方程；通过Pro/E软件建立发动机排气门实体模型；通过Ansys软件对发动机排气门传热特性进行有限元仿真，并就不同工况进行深入分析计算，确定变工况条件下发动机排气门的失效情况。
关键词：发动机；排气门失效；Pro/E；Ansys；有限元仿真
The analysis of heat transfer FEM simulation of the engine exhaust valve
ABSTRACT
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 high temperature and thermal load are the main reason of exhaust valversquo;s failure problem. So it is essential to analy heat transfer to prevent the failure of engine valve,and the main research methods are as follows：through the analysis and calculation of heat transfer theory can build fundamental equations of the engine exhaust vavle,through Pro/E can build the solid model of the engine exhaust valve and through Ansys can make the analysis of heat transfer FEM simulation of the engine exhaust valve,and the paper conducts depth analysis and calculation under different working conditions to confirm the conditions of losing efficacy of vavle.
