含表面裂纹T型叶根应力强度因子的数值计算  

Numerical Calculation of Stress Intensity Factors for Blade's T-root Part with a Surface Crack

作　　者：王立清[1] 盖秉政[1] 

机构地区：[1]哈尔滨工业大学航天科学与力学系,哈尔滨150001

出　　处：《动力工程》2008年第2期169-171,220,共4页Power Engineering

基　　金：国家自然科学基金资助项目(16272636)

摘　　要：采用三维有限元方法计算在离心力作用下T型叶根的应力强度因子.在有限元分析中考虑了T型叶根与轮缘的接触作用,应用位移相关技术计算了沿裂纹前缘各点的Ⅰ型应力强度因子.结果表明:在裂纹前缘Ⅰ型应力强度因子在极角α等于π/2时达到最大值;随着裂纹深度与裂纹长度比率的增大,裂纹前缘各点的Ⅰ型应力强度因子增加.这些结果对于叶根表面裂纹的扩展、剩余强度以及疲劳寿命的评估是非常有用的.The stress intensity factors of blade＇s T-root part under centrifugal actions is calculated by threedimensional finite element method. The contact interaction between blade root and disc rim is considered in the finite element analysis. The stress intensity factor of Ⅰ-type along each point of crack＇s leading edge is evaluated using the displacement correlation technique. The results show that the Ⅰ-type stress intensity factor at leading edge reaches the maximum value when the polar angle α is equal to π/2. With the ratio of crack depth to crack length increasing, the stress intensity factor of Ⅰ-type along each point of crack＇s leading edge increases. These results are quite useful for evaluating the crack growth, residual strength and fatigue life.

关 键 词：能源与动力工程 汽轮机 T型叶根叶片 有限元法 表面裂纹 应力强度因子 

分 类 号：TK263[动力工程及工程热物理—动力机械及工程]