Finite Element Analysis of Piston of a Marine Low Speed Engine Based on Fluid-Thermal-Structure Coupling

Abstract

The piston of low speed diesel engine works in bad environment and bears large thermal and mechanical load, so it is necessary to study the piston. In this paper, a Marine low-speed diesel engine piston as the research object, builds the piston component - crosshead assembly - connecting rod - crankshaft model, simulation of the piston in the working process of the actual working condition, through professional simulation software for fluid-thermal-structure coupling calculation, the temperature field and coupling stress field of piston assembly are obtained. In this paper, the convective heat transfer coefficient and fluid temperature on the surface of the piston cooling oil chamber are obtained by CFD simulation, the temperature field of the piston assembly is obtained by fluid-thermal coupling, and the coupling stress field and deformation of the piston assembly are obtained by fluid-thermo-solid coupling. Finally, the maximum temperature of the piston is 313.9°C, the maximum deformation is 1.03mm, and the maximum stress is 347.4Mpa, which meet the requirements.