摘 要

内燃机是现如今世界上应用最广泛的动力机械，其中常见的内燃机主要有两种。一种是我们在学习过程中经常接触的柴油机，另外一种是汽油机。内燃机从原理来看，它是通过燃烧机器体内燃料，然后将热能转换为机器动能的一种动力装置。内燃机活塞在高温高压燃气燃烧膨胀的压力推动下带动曲轴旋转作往复运动来让内燃机循环运转。在内燃机工作运转过程中活塞非常特殊且关键，活塞顶面是燃烧室的组成部分与高温高压燃气相接触，导致活塞在周期性运转工作时的热负荷较大。活塞的热负荷已经影响了内燃机在运转过程中的稳定性和可靠性。对内燃机活塞进行热负荷仿真研究已经是内燃机活塞设计优化提升的必要研究内容。在本文活塞热负荷数值仿真研究中以船用内燃机的某ω型活塞作为研究对象，进行活塞有限元仿真研究。

（1）通过三维建模软件SolidWorks建立活塞三维模型，介绍了相关的建模过程以及活塞基本参数，将活塞三维模型导入ANSYS进行活塞热负荷数值仿真研究。

（2）利用ANSYS Workbench有限元分析软件中Mesh应用程序对活塞进行网格划分，在稳态热分析模块中输入热边界条件进行后处理求解得到活塞的稳态温度场。

（3）利用ANSYS有限元分析软件对活塞进行热分析，通过分析后处理求解得出的温度云图深入分析研究活塞热负荷的相关情况，最后对活塞热分析的结果进行总结，为活塞的性能优化设计提升提供参考。通过与参考文献对比中发现活塞热负荷数值仿真研究的实验数据准确真实，对活塞的优化设计提升具有参考意义。

关键词：内燃机，活塞，热负荷，仿真研究，有限元

Abstract

Internal combustion engines are the most widely used power machinery in the world today, and there are two main types of common internal combustion engines. One is the diesel engine that we often contact during the learning process, and the other is the gasoline engine. From the point of view of the internal combustion engine, it is a kind of power device that burns the fuel in the machine body and then converts the heat energy into the machine kinetic energy. The piston of the internal combustion engine drives the crankshaft to reciprocate under the pressure of combustion and expansion of high-temperature and high-pressure gas to make the internal combustion engine cycle.

During the operation of the internal combustion engine, the piston is very special, and the top of the piston is in contact with the gas, so the thermal load of the piston is large. The thermal load of the piston has affected the stability and reliability of the internal combustion engine. The thermal load of the piston has affected the stability and reliability of the internal combustion engine during operation. Simulating the thermal load of the internal combustion engine piston has been a necessary research content for the optimization and improvement of the internal combustion engine piston design. In this paper, the piston thermal load simulation research takes the ω-type piston as the research object, and the finite element analysis of the piston is carried out.

(1) Establish 3D model of piston by 3D modeling software SolidWorks, The related modeling process and basic parameters of the piston are introduced. The three-dimensional model of the piston is imported into ANSYS to conduct numerical simulation research on the thermal load of the piston.

(2) Make use of Mesh application in the ANSYS Workbench software to perform the mesh generation, and after entering the thermal boundary conditions in the steady-state thermal analysis module for post-processing to obtain the steady-state temperature field of the piston.

(3) Use ANSYS finite element analysis software to carry out the thermal analysis on the piston. The temperature nephogram obtained by analysis and post-processing is used to analyze and study the heat load of the piston. Finally, review the results of the thermal analysis of the piston to provide references for performance optimization and design improvement of the piston. Compared with the references, the experimental data of the numerical simulation study on the heat load of the piston is accurate and true, which has reference significance to the design optimization of the piston.

Key Words：engine；piston；thermal load; simulation Research;Finite element