Study On Hydraulic Model And Water Quality Model Of Water Supply Network In A New Area

The urban water supply system is an important factor restricting urban development.With the rapid development of the city,the scope of the urban area continues to expand.As an important infrastructure of the city,the water supply pipe network system needs to be continuously updated and improved with the expansion and development of the city.Establishing and perfecting the hydraulic and water quality model of the water supply network is a new technical development direction of managing pipe network system.Taking the water supply network in some areas of a city as an example,the problems of water supply network aging,water pollution and pipe explosion in this area are frequently crop up,which can not be effectively solved.Meanwhile,the water quality safety can not be effectively guaranteed.To solve the above problems,it is necessary to understand the latest information in the pipe network timely and accurately Based on the field survey data,GIS system,CAD as-built drawing,and the basic data of the current situation of the pipe network provided by relevant technicians,this paper establishes a preliminary pipe network model and compares it with the actual pipe network conditions,and checks it manually to make the pipe network hydraulic model more accurate.Based on the basis of the completed hydraulic model,the water quality model of the pipe network is established.Two optimization algorithms are used to check and compare accuracy to obtain a more accurate algorithm.This study takes the water supply network of a new area as the object,and constructs the hydraulic model and water quality model with two algorithms to check the water quality model and compares the check results,so as to conduct an in-depth research.Firstly,the hydraulic model is constructed through the actual data and software platform.This paper introduces the basic principle of the hydraulic model of water supply network in detail,introduces each pipe network equation in the hydraulic model,and lists the solution method.Then,according to the GIS data and CAD graphics provided in the region,the collection of the actual data in the region is completed.The missing and defective parts will be supplemented by relevant technicians.Combined with the field survey results,the hydraulic model of the water supply network is established.To make the hydraulic model closer to the actual pipe network operating conditions,the model needs to be checked.The measured data of 9 typical pressure monitoring points are compared with the hydraulic model and the relevant parameters of the hydraulic model are corrected.The checked results show that the pressure error of all check pressure monitoring points is≤±4m,the accuracy of the checked hydraulic model is improved,and the error is controlled within an acceptable range.Secondly,the water quality model of the new area is established by using the first-order residual chlorine attenuation model and EPANET software through the built-in Lagrange time-driven method.The determination of the water quality model mainly focuses on the values of residual chlorine attenuation coefficient（K_b）of main water reaction and residual chlorine attenuation coefficient（K_w）of a pipe wall.The main water reaction coefficient K_bis mainly related to the initial chlorine concentration（C₀）,temperature（T）,total organic carbon（TOC）,and p H value,which can be calculated as-0.36 d^-1through mathematical expression while the determination of the residual chlorine attenuation coefficient k W on the pipe wall is based on the existing research results and the actual pipe network data.When the values of the main water reaction coefficient（K_b）and the attenuation coefficient of residual chlorine on the pipe wall（K_w）are determined,combined with the hydraulic model of the pipe network,then the water quality of the water supply pipe network in this area is simulated for 72 hours by EPANET software.Finally,to further improve the accuracy of the model,the two algorithms will be checked respectively,and a more accurate water quality model will be selected by comparing the accuracy.The attenuation coefficient of the model is automatically and randomly optimized by Matlab’s built-in genetic algorithm toolbox and standard particle swarm optimization algorithm combined with the EPANET toolbox.The genetic algorithm obtains the optimal solutions of Kw and Kb of each group after 100 iterations;The standard particle swarm optimization（PSO）performs 50 iterations.The above verification results show that both the genetic algorithm and PSO algorithm can make the verified model accurately reflect the operation status of the water supply network accurately.But the genetic algorithm is more accurate than the PSO algorithm and closer to the actual situation of residual chlorine at the nodes of actual water supply network.Figure[32]Table[15]See[112]...