重力坝下游宽尾墩和消力池联合消能工水力特性试验研究

某水电站是目前采用＂宽尾墩＋消力池＂联合消能工中坝高最大的水电工程,加之流量大,洪峰频率高,泄洪建筑物运用频繁,其泄洪消能问题十分突出。本文通过水工模型试验研究,对表孔宽尾墩体型设计参数进行了优化,同时对比分析了长、短消力池的流态、水面线、压力分布、临底流速等水力特性,提出了一个水力学较优的消能工体型布置方案。实测结果表明,消力池底板时均冲击压力高达42.9（9.81kPa）,脉动压力高达10（9.81kPa）.恰当增加消力池长度对于降低消力池出池水流波动和减轻下游河道冲刷有利。试验成果已为实际工程的消能防冲设计提供了重要的参考依据。

Experimental study of hydraulic characters of the flaring gate pier & stilling basin united energy dissipator with high water head and large discharge

The hydropower station presented in this paper is the highest dam project adopted "flaring gate pier and stilling basin" united energy dissipator in China,which was provided with the characters of large discharge,high flow flood emerged frequently,and flood discharging structures used frequently,so it is very important to study the problems about energy dissipation.In this paper,by hydraulic experiments,we optimized the structure parameters of flaring gate piers on surface spillway.Additionally,the hydraulic characters of short and long stilling basins were compared and analyzed,such as flow pattern,water surface,pressure distribution,close-to-bed velocity.The results show that the average impact pressure and the fluctuating pressure of the stilling basin bottom reach 42.9(9.81kPa) and 10(9.81kPa) respectively.It is also found that increasing the length of the plunge pool appropriately do well to reduce the flow fluctuation of stilling basin outflow and to lighten the flow scour of the downstream.So a relatively good flood discharging structures combination is proposed,which provides strong references for the design of energy dissipation.