梯级水库回水末端弯道取水工程泥沙淤积特性研究

Research on Sedimentation Characteristics of the End Bend Water Extraction Project of Cascade Reservoir Backwater

由于上下游梯级电站运行方式的协调性对取水河段的河床演变影响较大,导致水库回水末端弯道河段泥沙淤积特性复杂,通过比尺为λl=λh=100的推移质、悬移质正态模型试验,结合上下游电站的运行方式,探索取水河段的泥沙淤积规律,对梯级水库回水末端弯道取水河段的泥沙淤积特性进行了研究。结果表明,推移质泥沙主要淤积在河道右岸(凸岸),位于河道左岸(凹岸)取水工程蘑菇头布置位置无推移质泥沙淤积;当上下游电站运行不协调,悬移质将在取水河段落淤,由于扰流作用,取水口蘑菇头局部范围无泥沙淤积;安全敏感性分析表明取水工程的安全性可以得到保证。

Since the coordination of the operation mode of the upstream and downstream cascade power stations has a greater impact on the river bed in the water intake river section,which will lead to complex sediment deposition characteristics in the curved river section at the end of the reservoir.In this research,we conducted normal model tests of bed load and suspended load with a scale ofλl=λh=100,combined with the operation mode of upstream and downstream power stations,to explore the sediment deposition law of the intake section and then to study the sediment deposition characteristics in the intake area.The results show that the bed load sediment mainly accumulates on the right bank(convex bank)of the river,and there is no bed load sediment accumulation at the mushroom head layout of the water intake project on the left bank(concave bank)of the river.When the upstream and downstream power station operation is not coordinated,the suspended mass will settle in the water intake section and there is no sediment siltation in the local area of the mushroom head of the intake due to the disturbance effect.The safety sensitivity analysis indicates that the safety of the water intake project can be guaranteed.