多级孔板消能在大梁水库放水洞中的研究应用

大梁水库放水洞初步设计采用９级孔板消能，经水工模型试验证实，１５５ｍ水头可消减１３０ｍ，消减水头占总水头的８４％以上，消能效果显著，文中主要内容是孔板消能机理、布置原则、影响因素及设计试验成果，孔板消能设计中的关键问题是：（１）孔板孔口水头损失系数的选择，影响水头损失系数的因素有雷诺数Ｒｅ，孔径比ｄ／Ｄ，孔板间距及孔板形状等；（２）要求水流空化数大于初生空化数，以避免孔板产生空蚀、空化现象。

Research and Application of Maltistage Orifice Energy Dissipation in the Dewatering Tunnel of Daliang Reservoir

The nine-stage orifice energy dissipation has been applied to the design of dewateringtunnel of Daliang reservoir. Through the hydraulic model test, the 130m water head was reduced, fromoriginal 155m to 25m. The effection is so strong that reduced energy occupies 84 percent of total head.The key of the orifice energy dissipation design follows: (1) The choose of head loss coefficient in theorifice, which is decided by Reynolds number (Re), diameter ratio (d/D), distance between orificesand the shape of the orifice, ect. (2)Flow cavitation result must be larger than initial cavitation result,which protects the orifice from happening of cavitation and air erosion.