常州市主城区畅流活水方案模拟比选及现场试验研究

为了改善常州市主城区水环境，通过数值模拟计算与现场试验相结合的方法，开展畅流活水水环境提升方案研究。利用优质丰富的长江水作为引水水源，通过魏村枢纽和澡港水利枢纽引水，围绕新建工程大运河西枢纽及与4座活动堰工程的调度组合，设置了5组模拟方案，通过水动力数学模型，模拟各方案下城区内部河道流量分配情况，并结合现场试验论证了推荐活水方案的效果。结果表明:推荐方案形成了3级水位差、水位调控精准、流量分配合理的畅流活水格局，河网水环境改善显著，同时大部分水质指标在引水结束后16 d内均仍处于较好的状态，但部分河道的水质反弹明显。通过数学模型开展水动力调控是改善平原河网城市水环境的有效手段；但需要强化日常监测，根据水质变化情况合理确定活水周期，同时对部分水质异常点位开展污染源解析工作，保障河网水环境的长效久治。

Simulation and comparison of clean water diversion schemes in Changzhou main urban area

In order to improve the water environment of the main urban area of Changzhou City, through the combination of numerical simulation calculation and field test, the research on the scheme of improving the water environment of smooth flowing water was carried out. Using high-quality and abundant water from the Yangtze River as the water diversion source, the Weicun water conservancy project and the Zaogang water conservancy project were used to divert water. Five groups of simulation schemes were set for the new project of Daxi project of the Dayun River and the dispatching combination with four movable weir projects. Through the hydrodynamic mathematical model, the flow distribution of the river in the urban area under each scheme was simulated. Based on the field test, the effect of the recommended scheme was demonstrated. The results show that the recommended scheme has formed a smooth flow pattern of three-level water level difference, accurate water level regulation and reasonable flow distribution, and the water environment of the river network has improved significantly. At the same time, most of the water quality indicators are still in a good state within 16 days after the end of water diversion, but the water quality of some rivers has rebounded significantly. It is an effective way to improve the water environment of plain river network cities to carry out hydrodynamic regulation through the mathematical model. However, it is necessary to strengthen daily monitoring, reasonably determine the living water cycle according to the water quality changes, and carry out pollution source analysis for some abnormal water quality points, so as to ensure the long-term treatment of river network water environment.