基于流固耦合的混流式水轮机转轮强度分析

Strength Analysis of Francis Turbine runner Based on Fluid Structure Interaction

对我国东北某大型混流式水轮机在设计水头不同工况的转轮强度进行了单向流固耦合计算,采用CFD软件CFX,计算得到各工况流场中叶片表面的水压力,借助ansys workbench平台,将其作为结构面载荷加载到叶片上,得到各工况下转轮的静应力分布及变形情况。研究结果表明:转轮静应力最大值随着流量的升高而增大,且均出现在叶片出水边连接上冠位置附近;转轮最大变形量随着流量的升高而增大,最大变形量出现在下环位置。研究结果为混流式水轮机结构设计及安全运行提供了有效依据。

The runner strength of a large Francis turbine in northeast of China under three loading conditions with designed head is calculated by using the unidirectional fluid structure interaction method. The pressure on blade surface calculated by CFD software CFX is taken as the blade structure surface load, and then the runner strength is calculated by the ANSYS workbench. Finally, the static stress and deformation distribution of runner are obtained under different operating conditions. The results show that the maximum static stress increases with the increase of flow rate, and the maximum stress appears at the junction of runner crown and blade effluent side. The maximum deformation also increases with the increase of flow rate, and the maximum deformation appears on the runner band. The results can be referred by the researches who works on the structure design and safe operation of Francis turbine.