Study On The Hydraulic Characteristics At The Side Inlet/outlet Of The Upper Reservoir Of Pumped Storage Plant

The operation of pumped-storage power plants is both flexible and reliable. Besides the functions of filling valley and modulating peak, it undertakes many other tasks such as frequency modulation, phase modulation, emergency reserve etc. At present, the available pumped-storage power plants in China have demonstrated increasing importance in their own power network. In recent years, with the growing demand for electricity, the need for filling valley and modulating peak of the power system has been growing. Therefore, it is necessary to build the Pumped-storage power plants that can not only well fill valley and modulate peak but also can achieve the dynamic economic benefits. Pumped-storage power plants can be divided into plants with side inlet/outlet and vertical inlet/outle according to the forms of inlet and outlet. In China, the side inlet/outlet has a wide adoption with less extensive adoption in vertical inlet/outle.This paper describes mainly the side inlet/outlet of the upper reservoir of Fengning pumped-storage power plant. The hydraulic characteristics of the side inlet/outlet in the upper reservoir are analoged with three-dimensional k-εturbulent model.First,the original project of the side inlet/outlet of the upper reservoir of Fengning pumped-storage power station(type 1 and type 2) is investigated with three-dimensional k-εturbulent mode in the pumped condition and powering condition. The analysis and comparison of hydraulic characteristics, including head loss, flow distribution and velocity distribution,On the basis of the original project, to change the vertical diffusion angle of the diffusion portion to Optimize the project. The vertical diffusion angle plays an important role in modulating the water flow. The shrink of the diffusion angle can greatly optimize the asymmetry parameter of the velocity and the separation of the water flow in a certain degree.