水轮机迷宫环间隙不均诱发的结构振动特性研究

摘要

以某原型水轮机组受迷宫环间隙不均诱发的结构振动为研究对象，采用加权余量的伽辽金法建立其流固耦合的有限元方程，利用声学理论求解流固耦合方程。计算得到了水轮机座环在迷宫环不平衡水流作用下动力响应的双振幅值，讨论了水轮机座环的振动特性。计算结果表明：受结构自身刚度在各个方向的差异，座环横向振动幅值大大高于竖向；间隙不均在环向的分布特性对结构振动影响较大。%Taking the structure vibration of a hydropower station’s prototype hydroturbine unit induced by inequable labyrinth gap as a research object,the finite element equation of fluid-structure interaction is established by using the weighted residual Galerkin method so as to solve the fluid-structure interaction equation by using acoustic theory.The du-al amplitude values of hydroturbine seat ring are gained under the imbalance labyrinth water force,and the flow-induced vibration characteristics of the seat ring are analysed.The calculation results show that the lateral vibration amplitude of the seat ring is significantly higher than its vertical vibration amplitude,and the gap inequality in the distribution charac-teristics of the ring has an important impact to the structural vibration,which is mainly caused by the difference of the structure’s stiffness in different directions.