超超临界汽轮机高压转子低周疲劳及损伤分析  

Numerical Analysis of Low-Cycle Fatigue and Damage of a Ultra-Supercritical Steam Turbine High-Pressure Rotor

作　　者：赵乃龙[1,2] 吴穹[1,2] 王炜哲[1,2] 张军辉 

机构地区：[1]上海交通大学动力机械与工程教育部重点实验室,上海200240 [2]上海交通大学燃气轮机研究院,上海200240 [3]上海电气电站设备有限公司上海汽轮机厂,上海200240

出　　处：《上海交通大学学报》2015年第5期590-594,共5页Journal of Shanghai Jiaotong University

基　　金：国家自然科学基金项目(50906049)资助

摘　　要：为了评估国产某百万级超超临界汽轮机高压转子的高温强度,利用有限元分析软件Abaqus建立了超超临界汽轮机高压转子的轴对称有限元模型,加载了相应的热力边界条件,分析了转子在冷态启动过程中的温度和应力分布以及特征点的等效应变变化过程,并采用Mansoncoffin公式预测转子在冷态启停过程中产生的疲劳损伤.结果表明:在转子启动初期,凝结换热所导致的转子表面与转子中心的温差较大;在转子启动初期,转子受热不均匀所引起的热应力较大,在转子启动后期,其应力降至较低水平;高压转子在平衡活塞圆弧段产生的低周疲劳损伤最大,但其值仅为1.692×10-4,在所设计的使用条件(30a启停360次)下不会出现低周疲劳失效的危险.The axisymmetric high-pressure rotor of a ultra-supercritical steam-turbine was modeled by com- mercial finite element software Abaqus for assesment of its high temperature strength. The loaded thermo- mechanical coupling boundary condition, the temperature and stress distributions of the rotor, and the equivalent strain history of key points under cold start-up procedure were analyzed. The fatigue damage of the rotor during a start-up and shut-down cycle was predicted by the Manson-coffin formula. The results demonstrate that the temperature difference caused by comdensation heat transfer between the surface and center of the rotor is initially large. The rotor is affected more significantly by thermal stress, and uneven heating results in large thermal stress at the initial phase of the start-up procedure, while the stress re- duces during the later period of the start-up. Furthermore, the maximum fatigue damage occurs on the arc segments of the balance pistons, and the damage value is 1. 692 × 10^-4. Consequently, the danger of low- cycle fatigue failure should be ignored in application.

关 键 词：超超临界汽轮机 高压转子 低周疲劳 损伤分析 

分 类 号：TK263.6[动力工程及工程热物理—动力机械及工程]