阶梯溢流坝与二级消力池联合消能体型研究

On the Shape Effects of the Joint Energy Dissipator of Stepped Spillway and Two Cascade Stilling Basins

阶梯溢流坝以其较高的消能率被广泛用于工程中,但对其深入的研究尚少。通过数值模拟计算结合模型试验的方法,研究溢流坝的过渡台阶组合以及两级消力池入池体型对于溢流坝流速、流态、消能率等水力特性的影响表明:过渡台阶组合与消力池入池体型对整体消能率影响较小,阶梯溢流坝入流端采用小尺寸逐渐过渡到均匀尺寸台阶的组合能有效调整入池流态,消力池入池端采用斜坡代替台阶调整入池下跌水流角度,可减少对于消力池底板的冲刷,证明采用入池斜坡的阶梯溢流坝与二级消力池联合消能具有良好的消能效果。

Stepped spillway is widely used in engineering due to its high energy dissipation rate. While research on the joint energy dissipator of stepped spillway and two cascade stilling basins is still rare. In this paper, numerical simulation and model experiment are carried out to study the effects of the shapes of the spillway transition steps and the inlet of the two cascade stilling basins on hydraulic characteristics of the spillway such as the flow velocity, flow pattern and energy dissipation rate. The results show that the shapes of the transition steps and the stilling basin inlet are of small influence on the overall energy dissipation rate. The inflow pattern of the stilling basins is effectively improved by a transitional shape of the inlet of the stepped spillway from small steps to uniform size steps. The falling angle of the discharge flow into the stilling basins can be adjusted by replacing the inlet steps with a slope, which can further alleviate the scouring of the stilling basin floor. The joint energy dissipator of stepped spillway and two cascade stilling basins with slope inlet is proved to be good energy dissipation rate.