黄河中游水库群联合调控塑造高效输沙洪水探讨

Study on Integrated Regulation of the Reservoirs in the Middle Yellow River to Form Floods for High-Efficient Sediment Transport

基于三门峡水库、小浪底水库实测资料与数学模型计算成果,对黄河中游水库群水沙联合调度塑造高含沙水流进行研究,重点探讨了古贤水库建成运用后的影响,得出以下主要结论:(1)利用古贤水库提供可调水量冲刷三门峡水库并与小浪底水库错峰,可塑造小浪底水库最长历时的排沙过程,此方案下小浪底水库出库含沙量在50 kg/m^3以上的天数约为20 d,双库联合运用较单库运用含沙量大于50 kg/m^3的天数增加7 d;(2)利用古贤水库提供可调水量冲刷三门峡水库并与小浪底水库沙峰对接,可塑造小浪底水库最大出库含沙量,此方案下小浪底水库最大出库含沙量在400 kg/m^3以上,日均含沙量在200 kg/m^3以上的天数约为3 d,冲刷量增加1.8亿t。合理运用黄河中游水库群进行联合调水调沙,可有效塑造高效输沙洪水过程,并达到减少水库泥沙淤积的目的。

To speculate about the formation processes of hyper-concentration flows under joint operation of multiple reservoir systems in the Middle Yellow River , this paper conducted field measurements and physical experiments both in the Sanmenxia Reservoir and Xiaolangdi Reservoir. Based on these data sets , the paper also established numerical models and evaluated the role of the planning Guxian Reservoir in the joint operation of multiple reservoir systems. The results show that a ) when flows from the Guxian Reservoir scours the Sanmenxia Reser-voir , and staggered hyper-concentration flows in the Xiaolangdi Reservoir , the longest duration of sediment flushing will occur in the Xia-olangdi Reservoir. In this scenario , the period that sediment concentration of the outflows exceed 50 kg / m^3 can retain about 20 days , which is 7 days more than that the operation of single reservoir;b ) when flows from the Guxian Reservoir scours the Sanmenxia Reservoir , and keeps pace with hyper-concentration flows in the Xiaolangdi Reservoir , the maximum sediment concentration will occur in the outflows from the Xia-olangdi Reservoir. In this scenario , the maximum sediment concentration will reach 400 kg / m^3 and the period that sediment concentration ex-ceed 200 kg / m^3 can retain about 3 days , which leads to 18×10 8 m^3 in sediment erosion of the reservoir. The results in this study indicate that the water-sediment regulation scheme under joint operation of reservoir-group can lead to the formation of hyper-concentration flows and re-duce the sediment deposition in the reservoirs effectively.