Optimal Upgrading Design Of Urban And Rural Water Distribution System Based On Water Quality

Water distribution system plays an important role in urban infrastructure, directly affects the process of urbanization. In the context of urban and rural integrated development, carry out to study optimal upgrading design of urban and rural water distribution system based on water quality. Combined the theoretical point of view and engineering practice, provides a theoretical basis for the transformation of pipe network, could improve the efficiency of water distribution system, reduce the reconstruction investment and ensure the water quality of the end of the pipe network. In this paper, use the combined methods of theoretical analysis, numerical simulation and project example to research and explore.First of all, according to actual demand, established a water distribution system evaluation model with universal and better applicability, which could be able to master node pressure, water quality, running costs, system running reliability, pipe service life and so on. Based on the comprehensive analysis of existing information, assessed the operational status of water supply system, and selected the potential upgrading pipes, then proposed optimization program integrated investment economy, system operation reliability and water quality proteceion level.Secondly, tried to use a relatively new heuristic harmony search optimization algorithm to solve the optimal design problem. For the shortcomings of standard methods, proposed several improved measures to effectively improve the algorithm efficiency. Simulation tests of several typical functions and a water system example showed that the improved algorithm could efficiently and steadily find the best solution.Then, based on the study results of single-objective design, introduced the concept of network resilience to evaluate system operation reliability and used the integrated indicators to assess system safety, established a multi-objective optimization of mathematical model. According to the principle of Pareto dominance, proposed hybrid multi-objective optimization algorithm based on Max-min probability density. After got all the Pareto optimal solution set, used Topsis method for quadratic optimization. Simulation tests of several typical functions and a water system example also showed that the multi-objective functions founded was reasonable and the improved algorithm could efficiently and steadily converge to Pareto optimal front and find uniformly distributed Pareto set. Finally, combined informations of CAD, SCADA and GIS, established Jiaxing water distribution system model of urban and rural. The research results of previous studies were successfully applied to the model to evaluate the status of pipeline network, propose reasonable upgrading optimal program and provide a strong theoretical basis and technical support for the urgrading program of water supply system.