龚嘴水库坝前减淤调度的入库流量控制指标OA

The construction of the Pubugou hydropower station has caused erosion and deposition changes in Gongzui Reservoir,which has essentially reached the erosion-deposition balance.The impact of the operation and regulation mode on the erosion and deposition evolution of Gongzui Reservoir as well as the inflow control indicators of sediment reduction operation are examined in order to encourage sedimentation reduction of the reservoir in front of the dam. Based on the inflow water and sediment data from Shaping hydrological station,the changing trend of the runoff and sediment and the water and sediment situation of Gongzui Reservoir are analyzed,and the three typical water and sediment processes,namely abundant,flat,and dry,are determined.The two-dimensional mathematical model of water and sediment of Gongzui Reservoir is established,and it is verified that the model can accurately simulate the hydrodynamic process and the erosion and deposition distribution of Gongzui Reservoir by comparing it with the measured data.The erosion and deposition evolution in front of dams under the different typical water and sediment conditions and different operation and regulation modes is calculated based on the two-dimensional mathematical model,and the relationship between deposition-erosion amount and inflow rate is investigated. The findings show that:in large and average water years,lowering the water level at the right time helps reduce sedimentation in front of the dam;in small water years,the opposite is true.A high flow rate can wash sediment in the reservoir area toward the front of the dam.Additionally,lowering the water level aids in discharging sediment from the reservoir and helps decrease sediment buildup in front of the dam.Conversely,during small flow years,sediment cannot be discharged from the reservoir front due to insufficient hydrodynamic force,leading to sediment accumulation there.The critical flow rate for lowering the water level is 3 580 m3/s. In conclusion,using the critical flow rate for lowering water levels as the inflow control indicator in reservoir operation helps reduce sedimentation in front of the dam and does not affect normal power generation.Additionally,the current study can provide technical support for reservoir operations.