岩滩水电站3号机减振改造研究

本文通过对岩滩电站楼板强振原因和转轮裂纹的分析，针对岩滩电站的具体情况，通过采用负倾角叶片、增加叶片数、降低模型转轮最优单位转速和CFD分析等减振措施的应用，优化设计了A773a转轮用于岩滩电站减振改造。通过模型试验判断该转轮用于岩滩电站可以消除岩滩电站楼板强振；有限元分析结果可知消除了叶片裂纹；真机半年的运行和试验证明楼板强振消除。另外岩滩电站减振成功改造可以对其它大型机组的振动和裂纹问题提供借鉴和参考。

Research on decreasing vibration of No.3 turbine unit in Yantan water power plant

The factors resulting in the violent vibration of the power building floor and the crack of the runner are investigated under the practical situation of Yantan water power plant.Synthetical measures of adopting negative rake angle blades,increasing blade number,reducing optimum unit speed and CFD analysis are used to develop a new runner A773a that is replaced of the former runner to minimize the vibration level of hydroelectric sets in Yantan water power plant.The comparison test under the same conditions of model runner A773a and the former runner is carried out,the test result of runner A773a shows that the violent vibration of the power building floor may be eliminated.The results based on FEM(Finite Element Method) analysis approve that the crack of the runner is also avoided in Yantan water power plant.In addition,the proposed synthetical measures may be referable to other large hydraulic turbine units to minimize the vibration and crack.