汽轮机叶片疲劳寿命预测方法的研究  

Numerical Model for Steam Turbine Blade Fatigue Life

作　　者：谢永慧[1] 孟庆集[1] 

机构地区：[1]西安交通大学能源与动力工程学院,西安710049

出　　处：《西安交通大学学报》2002年第9期912-915,共4页Journal of Xi'an Jiaotong University

摘　　要：为了提高汽轮机叶片的可靠性 ,预防电厂中汽轮机叶片疲劳断裂的发生 ,首先提出了叶片应力和动态特性的数值分析方法 ,然后基于动态应力分析结果 ,考虑了影响汽轮机叶片失效的各种因素 ,引入Neuber准则和雨流计数法 ,建立了汽轮机叶片的疲劳寿命预测模型 ,并分析了一个 5片成组的 85 1mm叶片疲劳寿命状况 .结果表明 :提出的汽轮机叶片动态应力三维有限元分析模型具有良好的工程精度 ,叶片疲劳寿命预测可以定量地分析影响叶片安全运行的各种因素和叶片的疲劳寿命 ,为现实中叶片的设计制造及汽轮机运行提供了参考 .The most common failure mechanism of steam turbine blade is the normally forced vibration which results in the fatigue failure of blades, and it is important to increase the steam turbine availability by decreasing blade failures. This paper provides a numerical model to analyze the stress and dynamic characteristics of turbine blades. Based on the results of dynamic stress, and considering the reasons of blade failure and introducing the Neuber's rule and the rainflow counting method, a fatigue life evaluation method for turbine blade is developed. The 851 mm blade group is analyzed as an example. It is shown that the finite element analysis model has a good accuracy and it is suitable for the engineering application. The fatigue life analysis can give some quantitative results, and it is favorable to improve the reliability of blade under complicated operating environment of turbine.

关 键 词：寿命预测 汽轮机 叶片振动 动态应力 疲劳寿命 数值分析 疲劳断裂 叶片失效 

分 类 号：TK268.3[动力工程及工程热物理—动力机械及工程]