基于能量法的气缸盖低周热机疲劳寿命预测方法研究

通过测试气缸盖本体解剖试样，获得气缸盖材料的循环应力应变特性，并利用仿真方法验证其合理性。在此基础上，依据发动机低周疲劳台架考核方法，运用子模型分析技术，得到考核循环内气缸盖火力面的应力分布和塑性变形特性。基于塑性应变能理论，结合试验测试，对火力面低周热机疲劳寿命进行预测和评估，分析表明排气鼻梁区的寿命较低，约为1100次。

Low Cycle Thermo-mechanical Fatigue Life Prediction of Cylinder Head Based on Energy Method

The cyclic stress‐strain characteristics of cylinder head were acquired by testing the anatomical cylinder head speci ‐men and the feasibility of model was verified by the simulation method .Then the stress distribution and plastic deformation characteristics of cylinder head firing region were further acquired by using the sub‐model analysis technology according to the low cycle fatigue bench test method .Based on the plastic stain energy theory and testing ,the low cycle thermo‐mechanical fa‐tigue life of firing region was predicted and evaluated .The results show that the life of exhaust nose region is as short as about 1 100 times .