The Intensity Analysis In Piston Head Of The 6S50MC-C Diesel Engine

With the continues development of enhanced technology and supercharged technology of the internal combustion engine, the issue result from thermal load and mechanical load of internal combustion engine has drawn increasing attention. The designs of piston directly affect the engine performance, reliability and durability of use. In particular, the highly reliability required by marine diesel engine, any of the measures must be strengthened to ensure the reliability as a precondition. Therefore, the simulation of thermal load, mechanical load,coupled mechanical and thermal loads of the enhanced diesel engine to assess its reliability is important. Based on this consideration, using of large commercial finite element analysis software ANSYS, the thesis analyze piston head which under the action of coupled thermal load and mechanical load.In the paper, author firstly use Pro/E to establish the three-dimensional model of the MAN B&W 6S50MC-C diesel engine piston head. Then, author divides the model into ANSYS to mess. In imposing the boundary conditions, carried out simulation in ANSYS. First of all, the thermal field of the piston head is calculated by FEA software ANSYS. Based on the result of thermal field, thermal analysis, mechanical analysis, coupled mechanical and thermal loads analysis is executed on the piston head. According to finite element analysis, stress and strain distribution of the piston head was revealed by the ANSYS when coupled loads are applied. For instable operating conditions of diesel, calculated the boundary temperature and heat transfer coefficient using empirical formula and diesel engine indicator diagram which is the boundary conditions for calculating the piston head temperature field. In the thermal analysis module of ANSYS, temperature field of piston head is calculated. Based on the result of temperature field, thermal stress and mechanical stress on the piston head is executed. At last, the stress and strain distributions were calculated when the heat load and mechanical load is coupled. In addition, the article also analyzes the heat transfer situation in the piston head of diesel engine when the engine is starting. Course of transient changes in temperature curve of key nodes in the piston surface was calculated. This is conducive to further study such as the heat transfer and thermal shock in the piston head.Through the analysis of different loads, the stress field and deformation distribution is cleared. Stress concentration and deformation is mainly caused by thermal loads. Analysis of the heat, force and deformation, find the maximum stress and maximum deformation position which give a help to design engine, manufacture and management diesel. Summing up the characteristics, this can determine what caused the main deformation and stress. Basis of Course of transient changes in temperature curve of key nodes in the piston surface, calculate heat transfer law piston head when diesel engine begins to start. This is conducive to further study the piston head of the thermal shock and thermal fatigue for laying a solid foundation. By analyzing the piston in the steady-state conditions, the distribution of stress and strain and temperature variation under transient conditions, obtained in the process of engine design and management issues that need attention, and measures that the piston head to improve the strength. To further strengthen the design of diesel engines provide a theoretical basis.