低水头、大单宽流量泄洪消能方式研究

对于具有低水头、大单宽流量、低佛氏数、深尾水以及下游水位落差变幅大等特点的泄洪消能问题,其过流特点是:由于闸下跃前水流的佛汝德数较低,消力池内水垫较深,水流下泄后下游水位对闸室水流和消力池内水流流态影响较大。通过水工模型试验研究,提出了采用淹没式宽尾墩消力池联合消能方式。在闸室末端采用宽尾墩后,水舌沿纵向拉伸扩散,消除和抵消了常规的等宽闸墩情况下出现水跃的来回震荡现象,水流经宽尾墩收缩后,以淹没射流形式进入消力池,池内水流具有三维射流特性,消力池内产生横、纵向扩散和剪切、掺混,加强了消能效果,达到了稳定水跃、分散水流、加强紊动剪切和掺混的目的,较好地解决了下游河床的消能防冲问题。

Research and Test for Energy Dissipation Form of Low Head, Large-unite Discharge Flood Discharging

The energy dissipation of flood releasing with low head, large-unit discharge,low Froude,deep tail water and large drop ranges of downstream flow has following characteristics. Duo to low Froude in the frond-jump flow, the water cushion inside plunge pool is deep. After water flow releases to the downstream, the downstream head will bring big effect on the flow patterns in gate chamber and in plunge pool. Based on hydraulic model tests, a new submerged flaring pier energy dissipation tool was put forward. The test results indicated that submerged wide tail pier reduced and eliminated the oscillation of gate chamber current. On the bottom of gate chamber water flow submerges into plunge pool and the three-dimensional submerged flow diffusion is more sufficiency than the traditional type. So it could solve better the problem of energy dissipation and erosion of downstream bed and bank.