Study On Calibrated Parameters Of Urban Water Distribution System Model

In order to fully understand the actual operating condition of the water distribution networksystem, we build the water distribution system network model.So the model can assistant inour daily work including scientific management, optimal operation scheduling, optimizationexpansion, leakage control and water quality analysis, as well as the diagnosis of networkanomalies.And to improve network operation and management level and service levelIn the process of assembling the model, calibrating is the most important part. However, theinitial establishment of the water distribution system model may no match the real worldsystem, the reason is due to the early model, a variety of parameters, and there are some errorsin the input data. Therefore, to establish a more accurate water distribution system model, themodel must be checked, and reach a certain calibration standards, so that the hydraulic modelof the hydraulic characteristics can be compared to the real world network system.When we conducting the model calibration, we focus on the adjustment of the node demandand pipe roughness coefficients, and we ignore the uncertainty of diameter. The diameters ofpipes are reducing over time, due to the pipeline corrosion. We study on the Hazen Williamformulas and use random sampling for quantitative analysis of node demand, pipe diameterand pipe roughness coefficient. It turns that the diameter of the uncertainty also has asignificant impact on the state of the water distribution system network. The uncertainty ofdiameter needs to be considered in the model calibrating.After calibrating the diameter parameters, the complexity of the problem increases. We designthree different calibrate program with a benchmark network system. The results showed that,ignoring the uncertainty of diameter, will reduce the accuracy of the model. With the diameterconsidered, the improved accuracy of the model can achieve. In the calibrating process, Boththe way of calibrating pipe diameter and roughness coefficient in the same time or the wayfirst calibrate diameter then calibrate roughness coefficient were similar, can be used as areference check of two types of parameters.