利用有限元对6200柴油机功率提升前后缸盖强度的对比分析

建立了6200柴油机缸盖的实体模型和有限元模型，利用发动机热力仿真软件、CFD软件与有限元软件的交叉计算为气缸盖的强度计算提供了温度场和传热系数分布等边界条件。在此基础上，对柴油机功率提升前后气缸盖在预紧工况、热-机械耦合作用及爆发-热-机械耦合作用下承受的最大拉应力情况进行了计算分析，确定了各影响因素在缸盖上产生最大拉应力的主要位置。对气缸盖的疲劳强度安全系数进行了计算分析，为生产部门进行柴油机功率的提升提供了理论参考。1000h的可靠性实验证明了计算结果的合理性。

Comparative FEM Analysis for the Intensity of Cylinder Head of 6200 Diesel Engine During the Power Increasing Process

The solid model and finite element models of cylinder head for CW6200 diesel engine are given by means of the advanced simulation techniques, and the fields of temperature and the distribution of heat transfer coefficients are simulated by the engine thermal simulation soft package and the CFD soft package. And according to the calculated results, the highest stress of cylinder head under the working conditions of a mechanical loading, a thermal - mechanical coupled one and a thermal - mechanical coupled one with gas force are simulated during the power increasing process, and then the results help to find the places where the highest stress exists. Further more, safety factors of the places where failures might happen are calculated and analyzed, and provide the reference of the diesel power increasing for the manufacturing departments. The calculated results are proved to be reasonable by the reliable test of 1 000 hours.