水泵水轮机水泵工况顶盖下腔特殊压力脉动模型试验研究OA

With the accelerated construction of pumped-storage power plants,high-head and large-capacity pumped-storage units have gradually become the mainstream in development.During the operation of some high-head and large-capacity pumped-storage units under pump conditions,pressure pulsation with special frequency was detected in the lower cavities of head covers,which has attracted wide attention in the industry.In order to further reveal the underlying mechanisms of this phenomenon,a model test study on the special frequency of the lower cavities of head covers was conducted by altering the flow regimes in channels using a disturbing method.The test results show that the pressure pulsation in the lower cavities of head covers and vaneless zones is changed by disturbing the flow regimes in vaneless zones,and the amplitude and area of special frequency are decreased.The special frequency pressure pulsation in the lower cavities of head covers under pump conditions is mainly affected by the flow regimes in vaneless zones,and less affected by the flow fields in the lower cavities of head covers.