白虎潭水库溢流坝泄洪消能方式研究

Discussion on energy dissipation pattern of spillway for Baihutan reservoir

白虎潭水库溢流坝采用挑流消能,溢流堰面采用WES堰型。原挑流鼻坎采用常规等宽鼻坎,挑流水舌入水宽度大于下游河床宽度,水流落入下游河道后,落水集中,造成下游河床及岸边冲刷严重。经水工模型试验研究,推荐的台阶式堰面+差动挑坎+边墙末端局部收缩方案,使下泄水流归槽宽度减小、纵向及竖向充分分散,水舌入水面积增大,消能率增加,下游河道消能问题得到了有效地解决。

Ski jump energy dissipation is provided for the Baihutan reservoir spillway, and its overflow weir surface is of WES type. In the original option, the flip bucket is of conventional equal-width bucket, the width of deflecting nappe into water is larger than the width of the downstream riverbed, and the water flow is concentrated after falling into the downstream river channel, which causes heavy scouring to the downstream riverbed and the banks. Through hydraulic model tests and comparison of many alternatives, the alternative of step weir surface plus differential bucket and local contraction of side wall ends is recommended, which reduces the width of the trough for discharge flow, fully disperses the discharge flow in longitudinal and latitudinal directions, and increases the area of nappe into water, therefore, the rate of energy dissipation is increased and the energy dissipation problem in the downstream river channel is effectively resolved.