人民黄河

汛期是多沙河流水库调控水沙的关键时期,以往研究和实践中,多以定性或宽泛指标描述水沙调控。因此,建立度量指标体系,研究多沙河流水库汛期水沙调控度对科学认知水库调控能力、指导水库设计运用具有重要意义。根据黄河水沙调度实践,分别定义多沙河流水库汛期径流调控度和泥沙调控度指标,并给出相应的计算公式;采用1986年以后汛期来水来沙条件,分析黄河中游干支流水库汛期水沙调控度大小,发现现状已建水库调控度较小、调控能力不足,规划和在建水库调控度较大;进一步采用数学模型对比分析不同水库运用方式对汛期水沙调控度的影响,结果表明:"蓄清调浑"运用方式相比"蓄清排浑"运用方式,不仅可以有效减小不同时期库区泥沙淤积量,而且能够实现部分拦沙库容再生利用,从而增大水库汛期水沙调控度。

Flood season is a critical period for reservoirson sediment-laden rivers to regulate water and sediment. In previous studies and practice, qualitative indicators are widely used to describe regulation degree of water and sediment. Thus, establishing an accurate or relatively accurate measurement index system and studying regulation degree of water and sediment of reservoirs on sediment-laden rivers in flood season is of great significance for understanding regulation capability of reservoirs and guiding design and operation of reservoirs. According to the practice of water-sediment regulation in the Yellow River, the runoff regulation degree and sediment regulation degree were defined respectively, also the corresponding calculation expressions were given; the incoming conditions of water and sediment were used to analyze the regulation degree of water and sediment of reservoirs on the middle reaches of the Yellow River. It was found that the existing projects had a smaller regulation degree and insufficient regulation ability, while the regulating projects to be built or under construction had a larger regulation degree; the mathematical model was further used to compare and analyze the influence of different reservoir operation modes on the change of regulation degree of water and sediment in flood season. The results show that comparing with “storing clean water and discharging the muddy”, “storing clean water and regulating the muddy” can not only effectively reduce the amount of sedimentation in the reservoir in different periods, but also realize the regeneration of part of the reservoir capacity, thereby improving the regulation degree of water and sediment of reservoir in flood season.