潮汐河网闸泵联合调度的水环境效应数值模拟

Numerical simulation on effects of gate-pump joint operation on water environment in tidal river network

在已建立的西北江三角洲潮汐河网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、石啃的闸泵站联合调度引水情景下佛山水道的水质改善效果。计算结果表明:(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会造成明显的顶托作用,当沙口泵站引水流量小于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,要达到较好的水环境效应,沙口泵站引水流量应在30m3/s左右,而石啃泵站引水流量应控制在20m3/s以下。

A numerical model for water quantity and quality was developed to simulate the effects of joint gate-pump operation on water environment in the Foshan fiver course in dry seasons. In the model the COD was adopted as the indicator of water quality. The results indicate that： （1） The clean water diverted by the Shakou Pumping Station can well improve the water quality of the river course. （2） The clean water pumped by the Shiken Pumping Station performs well in the improvement of water quality of the upper reaches of the river. However, the Shiken Pumping Station can cause the deterioration of water quality of the upper reaches. When the discharge of the Shiken Pumping Station is smaller than 10m3/s, the deteriora- tion of the water quality can be observed in the Jiebian cross-section. （3） To obtain better water environ- mental effects as a result of water diversion by pumping needs sound joint operation of gates and pumps, the discharge of the Shakou Pumping Station should be around 30m3/s, and that of the Shiken Pumping Station should be about 20m3/s.