环形薄壁堰堰首竖井水力特性研究——以安徽绩溪抽水蓄能电站竖井溢洪道工程为例

Study on hydraulic characteristics of vertical shaft with annular thin-wall weir:case study of vertical-shaft spillway of Jixi Pumped-Storage Power Station

一般水利工程的溢洪道,大多采用岸边式,但当两岸山体布置岸边溢洪道存在山脊单薄、岩体风化深、开挖量大等不利地形条件时,可采用开敞式竖井溢洪道的形式.而竖井进口水流流态的好坏直接影响竖井的结构稳定和消能效果.以安徽绩溪抽水蓄能电站为例,通过模型试验,对竖井4种不同堰首结构的水力特性进行了对比研究.结果表明,采用一种新型环形薄壁堰首结构,在堰顶设置4～6个隔墩,将堰项分成对称的溢流表孔环形进流,能有效改善水流流态、降低水流对竖井壁的冲击,提高竖井的安全稳定性.

The flood spillway of hydraulic project is commonly constructed on the bank side, but for the unfavorable terrain conditions such as thin mountain ridge, deep weathered rock mass, large excavation quantity etc. , open channel shaft - spillway can be adopted. The flow state at entrance of a shaft will directly influence the structure stability and energy dissipation effect. Taking Jixi Pumped - Storage Power Station in Anhui Province as an example, the hydraulic characteristics of 4 weir heads are re- searched by the model test. The results show that a new type weir head of annular thin - wall weir with 4 - 6 separation piers can separate the flow on weir crest to symmetrical annular inflow, and effectively improve flow state, reduce flow impact to shaft wall, improve the safety and stability of the shaft.