调水对改善浅水型湖泊水体的置换率研究

Improving water exchange rate of shallow lakes through water diversion works

以郑州龙湖为研究对象,采用任意无结构网格拟合多连通水域,贴合不规则湖岸边界与湖内岛屿的外形,建立了沿水深平均二维水流和交换率数学模型。以寻求湖泊最佳的流态分布和实现水体的高效置换为目标,进行了多种调水方案水体置换率计算,实现了方案的最优化。该研究对城市浅水型湖泊采用调水改善湖泊水环境的类似研究具有一定的借鉴意义。

Appropriate water diversion is one of the most effective methods of improving water environmental quality in lakes, especially urban lakes. Due to landscaping, urban lakes tend to be quite irregular in configuration and usually have many islands. They also generally have the common characteristic of shallow lakes： their horizontal scale is much larger than the vertical scale. A two-dimensional depth-averaged flow and water exchange rate model was established for Longhu Lake in Zhengzhou City. The unstructured mesh of this model makes it fit for irregular boundaries and islands. Regarding the optimal flow pattern of the lake and the highest water exchange rate as an objective function, the method was optimized through calculation of water exchange rates under various water diversion schemes. This research can be applied to the modeling of other urban shallow lakes during water diversion.