潮汐河网区闸泵联合调度引水冲污数值模拟

在建立西北江三角洲潮汐河网区水量水质数学模型基础上，以COD为水质模拟因子，模拟分析了枯水期沙口、石啃水闸泵站联合调度引水下佛山水道水环境效应。研究表明：(1)上游沙口泵站引水对河道上、下游水质均有一定改善效果；(2)中游石啃泵站引水能明显改善下游水质，但由于其引水对佛山涌涌口以上河段的水流造成明显的顶托作用，当沙口泵站引水量小于10m3/s时，随着石啃泵站引水量的增加，街边断面水质反而变差；(3)综合考虑各种引水方案下的水量水质模拟结果，要使达到较好的水环境效应，沙口泵站抽水流量应在30m3/s左右，而石啃泵站抽水流量应控制在20m3/s以下。本文研究为潮汐河网区引水冲污决策提供科学依据与理论支撑。

Numerical simulation of water-diversion-induced pollutant dilution in the tide river networks

In this study, we developed numerical model for water quantity and quality, and analyzed the environmental effects of water diversion in the Fuoshan river channel in dry seasons. The results indicated that: (1) the clean water introduced by the Shakou pump station can well improve the water quality of the study river reach; (2) the clean water pumped by the Shiken station performs well in the improvement of water quality of the upper reaches of the study river. However, the pushing effect of the flow due to water diversion by the Shiken pump station caused deterioration of water environment of the upper reaches of the study river. When the discharge of the Shiken pump station is smaller than 10m3/s, the deterioration of the water environment can be observed in the Jiebian cross-section; (3) to obtain better environmental effects as a result of water diversion by pump stations needs sound joint operation of pump stations: the discharge of the Shakou pump station should be around 30m3/s; and that of the Shiken pump station should be about 20m3/s. The results of this study can build the scientific ground for the improvement of water environment in the tide-impacted river channels.