基于一维水沙模型的水库冲沙方式优化研究

在天然河流上修建水库,破坏了河流水沙原本相对平衡的状态。泥沙进入库区后发生落淤,从而导致水库淤积。在水库的实际运用中,冲沙措施被广泛用于减缓水库的淤积速率。然而,冲沙需要耗费水库较多的水量,影响了水库的综合效益,为此必须协调水库淤积与水库兴利效益之间的关系。在选定合理冲沙水位和冲沙流量范围的基础上,应用一维非均匀流不平衡输沙模型,结合某多沙水库现行调度规程,对多种拟定冲沙方案下该水库的冲沙过程进行长期模拟,计算各方案下水库多年平均淤积量和多年平均发电量等指标,据此选取合适的冲沙方案。结果表明,持续时间较长的低水位冲沙方式的冲沙效果相对较好,能够在一定程度上减缓水库的淤积速率,同时发电量的损失也相对较小。

Optimization research of reservoir flushing scheme based on one-dimensional numerical model

Building reservoirs on a river breaks the original balance of flow and sediment. Once the incoming sediment begins to deposit, a siltation will take place in the reservoir area. To slow down the siltation, reservoir flushing is widely used in the reservoir operation. However, reservoir flushing would inevitably waste too much water of a reservoir, damaging the comprehensive benefits of the reservoir. Therefore, the relationship between siltation and benefits must be balanced. As for a certain reservoir, on the condition that the current operation regulations are obeyed, a long-term numerical simulation of flushing process is conducted for different flushing schemes, in which the reasonable ranges of water level and discharge of flushing are proposed, by adopting an one-dimensional non-uniform flow and non-equilibrium sediment transport model, and the multi-year average amount of siltation and electricity generation are calculated to be the indices of the selecting of appropriate flushing schemes. The results indicate that the flushing scheme of a lower water level and a longer duration has a better effect on slowing down the siltation in the reservoir area, with the loss of electricity generation relative small.