采用水力模拟方法研究了某水库泄洪放空洞泄流状况及下游消能、冲刷、流态等问题.由于该泄洪放空洞属改建,轴向布置与下游河道边界不相适应,挑射水流人河后顶冲下游河道右岸防护堤,引起强烈的涌浪波动,以致壅高水位并造成流态紊乱,直接威胁堤防.通过分析研究,提出了将挑流鼻坎向左转角32°的优化方案,并采用束窄出口及圆弧扭面衔接的技术,调整挑射水流方向,有效保证了下游消能安全,同时避免了主流顶冲右岸堤防;由于消除了拦沙坎,下游出流平顺,边岸涌浪基本消失,大大降低了下游洪水位,削减了边岸回流强度与淘刷,保证了右岸施工营地的安全.
In this paper, the discharging, energy dissipation, scouring depth and flow regime in the downstream of spillway tunnel of a reservoir are researched by using the hydraulic analogy method. Due to the tunnel' s reconstruction, it is disharmony between the axial arrangement and downstream river boundary. Therefore, the shot flow scours on the right-bank bulwarks of downstream river and causes strong surge flu,'tuations. As a result, water level is risen up and flow pattern becomes disordered so that embankments are threatened directly. Through the analysis research, an optimized project of turning the flip bucket to the left by 32~ is put forward. Through adop- ring the techniques of shrinking exit and arc twisted surface convergence to adjust the direction of shot flow, the safety of the down- stream energy dissipation is guaranteed effectively, and meanwhile, the mainstream rushing on the right embankments is avoided. In addition, clue to the sediment storage dam's elimination, the downstream flow becomes smooth and shore-side surge almost disappears. Thus, this will greatly reduce the downstream flood level, cut side shore reflux intensity and scouring brush and ensure the safety of the right bank of the construction camp.