基于能量法的缸盖低周热疲劳寿命预测  

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

作　　者：张亚鲁 胡玉平[1] 李国祥[1] ZHANG Yalu , HU Yuping , LI Guoxiang(School of Energy and Power Engineering, Shandong University, Jinan 250061, China)

机构地区：[1]山东大学能源与动力工程学院,山东济南250061

出　　处：《内燃机与动力装置》2018年第3期17-22,共6页Internal Combustion Engine & Powerplant

摘　　要：用材料在低周载荷下形成的滞回能量作为预测结构高温低周疲劳寿命的损伤参量,通过对发动机缸盖材料施加循环热负荷,获得材料基于能量法的低周寿命预测模型参数;采用有限元分析方法对发动机单缸进行典型工况分析,并根据发动机启停循环中温度和应力的变化规律,结合子模型技术获得单个工作循环内缸盖火力面区域的温度场和应力场;对缸盖火力面附近区域进行循环加载,得到迟滞回线,评估其低周疲劳寿命。结果表明,在缸盖火力面进-排气门之间的鼻梁区低周疲劳寿命较短。The hysteretic energy of the material was expressed as the stress-strain response hysteresis curvewithstand low-cycle load . The hysteresis energy of the material withstand low-cycle loadis were considered to be the damage parameter for predicting the low-cycle fatigue life. The parameter of the low-cycle life prediction model based on the energy method was obtained by applying a cyclic heat load to the material of engine cylinder head. The temperatre and stress fields in the area of the fire surface of the typical operating conditions in the engine work cycle of a single cylinder are determined by applying the finiteelement method and the sub-model technique. Using the hysteresis curve obtained by the cyclic loading on the firesurface evaluate low-cycle fatigue life of the cylinder head. The results show that the low-cycle fatigue life is shorter in the nasal bridge region between the intake valvesand exhaust valves of the cylinder head.

关 键 词：气缸盖 能量法 有限元 低周疲劳 迟滞回线 子模型 

分 类 号：TK423.2[动力工程及工程热物理—动力机械及工程]