相关参数对汽轮机低压叶片疲劳寿命的影响  

Effect of Relative Factors on Fatigue Life for Low Pressure Blades of Steam Turbines

作　　者：徐自力[1] 李辛毅[1] 安宁[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：《动力工程》2004年第1期33-36,共4页Power Engineering

摘　　要：根据汽轮机低压叶片所受载荷的特点,建立了一种基于三维有限元法和改进局部应力应变法的叶片疲劳寿命预测模型。该模型定量考虑了频率的分散性、激振力因子、阻尼、疲劳缺口系数、表面粗造度、腐蚀、表面硬化状态、以及微动磨损等参数对叶片疲劳寿命的影响。给出了计算模型中这些相关参数的选取范围和选取原则。并用实例说明了该模型的可用性,计算也表明叶片疲劳寿命对这些参数的变化很敏感。该研究为叶片的事故分析和设计提供了一个有效手段和工具。According to the characteristics of loads on blades, a model for estimating fatigue life of blades is presented based on three-dimensional finite element method and improved local strain method. In the model, the effect of factors, such as the scatter of natural frequency, exciation index, damping, fatigue notch factor, surface roughness, corrosion, surface hardened stastus and micro-slip wear etc., on the fatigue life of blades are quantitatively considered. Values of these factors in the model are recommended. The fatigue lives of one blade with length of 680mm under different conditions are calculated and analyzed. The results show the fatigue lives of blades are very susceptible to these influencing factors. The study provided and effective way for trouble shooting of blade fatigue damage, and offered an approach for engineers to consider these factors that can seriously influence on blade life in design stage. Figs 2, tables 6 and refs 4.

关 键 词：动力机械工程 汽轮机 叶片 疲劳寿命 局部应力应变法 有限元法 

分 类 号：TK263.3[动力工程及工程热物理—动力机械及工程]