城市供水管网的试验模型研究

Research on Experimental Model of Water Distribution System

为便于研究城市供水管网中管流的水力特性和水质情况,依据水力相似原理,构建了与实际供水管网等效的管网试验模型。先分析并确定了压力供水管网符合欧拉相似准则,然后基于管流的变态相似理论,推导出管网原型与其试验模型间各物理量的相似关系。通过选定合适的几何比尺,建立供水管网试验模型。应用EPANET软件模拟管网模型运行工况,得到各节点的水头,据此调节各用户端电动球阀的开度,实现用户节点流量的试验模拟,同时应用EPANET软件模拟管网原型的运行工况。通过对比管网试验模型和原型中各相应管段的流速,验证了试验模型和原型能够很好地满足相似关系,表明该建模方法是可行的。

To facilitate a study on hydraulic properties and water quality in the urban water distri- bution system, an experimental model of an actual pipe network was established based on the hydraulic similarity principle. The pressure pipe network was analyzed and determined to meet the Euler similarity criteria. Similarities between the experimental model and the actual pipe network were derived based on the distorted similarity theory of pipe flow. Through selecting proper geometric scale, the experimental model of the water distribution system was built. The operating condition of the experimental model was simulated by EPANET to determine the water head at various nodes. Experimental simulation of flow rates at various nodes was implemented by adjusting the opening of electric ball valves. The operating condition of the actual pipe network was also simulated by EPANET. The flow velocity in pipes in the experimental model was compared with those in the actual pipe network. The results indicated close similarities be- tween the experimental model and the actual pipe network, suggesting that the modeling was feasible.