窄深河谷大夹角泄洪洞挑流消能方案的试验研究

Experimental Study on Energy Dissipation Scheme of Spillway Tunnel with Large Angle in Narrow and Deep Valley

新疆玉龙喀什水利枢纽工程位于高山峡谷区,1#深孔出口消能面临窄深河槽、浅水垫、岸坡稳定等不利条件。为了达到安全有效的挑流消能效果,避免或改善上述不利条件带来的制约和安全影响,对1#深孔出口开展模型试验研究。根据试验得到挑流消能流态、流速、冲淤、雾化等特性,分析其消能效果,优化挑流消能工体型。经试验研究,原设计正挑坎方案河道上游淤积不明显,水舌落点较为集中并偏于右岸,岸坡淘刷带来的稳定问题突出;通过调整挑坎左、右侧边墙半径等参数优化试验,最终采用"左挑右俯、分层出流、纵向拉伸"的挑坎体型,冲刷坑深度、岸坡淘刷问题显著改善,雾化影响也较小,有效解决了窄深河槽空间严重不足带来的安全问题。依此,为同类工程泄水消能工体型优化设计提供借鉴。

In the high mountain gorge area of the Yulongkashi water control project in Xinjiang,the outlet energy dissipation of the 1#deep hole is faced with such unfavorable conditions as narrow and deep channel,shallow water cushion and stable bank slope.In order to achieve a safe and effective energy dissipation effect of jet ski jump and improve the restriction and safety impacts caused by the above adverse conditions,a model test was carried out on the outlet of 1#deep hole.According to the characteristics of flow pattern,velocity,scouring and silting,atomization and so on,the energy dissipation effects is analyzed,and the structure of the energy dissipator is optimized.According to the experimental study,the upstream siltation of the original design is not obvious,and the landing point of the water tongue is more concentrated and inclined to the right bank,so the stability problem caused by bank slope scouring is prominent.By adjusting the radius of the left and right side walls and other parameters of the flip bucket,the flip bucket shape of"left flip and right dip,stratified outflow and longitudinal stretching"is finally adopted.The problems of scour pit depth and bank slope scouring are significantly improved,and the atomization effect is small,which effectively solves the safety problems caused by the lack of strict space in narrow and deep channels.