轴流式水轮机叶片刚度和强度有限元分析

轴流式水轮机转轮叶片进出口边与枢轴法兰连接的根部易出现应力集中。本文利用ANSYS有限元计算程序对某轴流式水轮机叶片的刚度和强度进行详细的计算分析，提出开应力缓冲槽的改进方案，并进一步探讨应力缓冲槽的形状、大小对降低应力集中效果的影响；在此基础上，提出加大叶片与法兰交接处过渡圆弧的改型方案，对改型前后叶片的应力、变形及模态分析表明，改型后的叶片应力集中显著改善，刚度和固有频率变化较小。

FINITE ELEMENT ANALYSIS OF STIFFNESS AND STRENGTH FOR AXIAL-FLOW HYDRAULIC TURBINE BLADE

Stress concentration often happened along the junction of some axial-flow hydraulic turbine blade and flange of pivot. This paper detailedly calculated and analyzed the stiffness and strength of a hydraulic turbine blade with finite element method, presented a transitional notch method, and then discussed the effect of notch shape and size on the decrease of stress level. And another remodeling project of seemly increasing transitional circle of blade root was put forward. The finite element analysis results of stress, displacement and mode for the remodeled blade indicate that stress level is lower, and the stress concentration is improved obviously. But compared with original blade parameter, natural frequency and stiffness of the remodeled blade change slightly.