Research On Optimization And Traceability Of Water Quality Monitoring Stations Based On Exogenous Intrusion Risk

The urban water supply pipe network is an important infrastructure project to maintain urban safety.To meet the needs of production and living,the water supply industry has been developed from simply increasing the water supply to improving the safety and economic benefits of water supply and strengthening operational management.The optimization of water quality monitoring stations and the source of external pollution under the coordinated monitoring of internal and external pollution of water supply networks has been a difficult problem in the field.In order to further improve the scientific rationality of the site selection of monitoring stations,this paper selected Modena urban water supply pipe network as the research object,studies the optimal location model of water quality monitoring stations based on exogenous intrusion risk,traceability model of external pollutants,and related Model optimization algorithm.Finally,the water quality monitoring and control scheme and the rapid traceability approach of the water network monitoring system are improved,and the monitoring and traceability of the water supply network monitoring system for the invasion of external pollution is improved.The main research contents of this paper are as follows:Firstly,the hydraulic model and water quality model theory and construction method of the water supply network are introduced.The hydraulic model of the quasi-steady water supply network of the Modena pipe network is constructed on the EPANET2 software platform,and the working conditions of the pipe network are analyzed.Based on the pipe network model,the MATLAB software is used to extract the dynamic and static data of the pipe network,combined with the urban infrastructure planning and topographic information of the water supply pipe network to analyze the risk of external invasion of the pipe network,and the fuzzy mathematics method is used to analyze the pollutants in the pipe network.The integrity of the pipeline and the low negative pressure of the pipeline network quantify the node risk assessment index of the pipeline network under the invasion of external pollution.Secondly,the paper introduces the construction process of the optimal site selectionmodel for water quality monitoring stations in the traditional water supply pipe network,and summarizes and analyzes the principles and expressions of the optimization objectives of three types of commonly used composite monitoring sites,namely,"monitoring failure rate","water coverage" and "monitoring station proportion".Based on the pipe network node risk assessment index,a new optimization target "node monitoring time expectation value" is formed.After the necessity analysis,the optimization target is included in the monitoring station optimization location model to improve the location optimization system,and the multi-objective optimization location model based on the external intrusion risk is established.Thirdly,two kinds of evolutionary algorithms for solving multi-objective optimization models are introduced: non-dominated sorting multi-objective genetic algorithm(NSGA-?)and reference vector-based non-dominated sorting multi-objective genetic algorithm(NSGA-?).Based on the optimization of the location model of the traditional water supply network,two algorithms are used to solve the problem.By comparison,the NSGA-? algorithm saves 58% of the computation time compared to NSGA-?.In the spatial distribution of the solution results,the former It is 6% higher than the latter,which proves that NSGA-? algorithm has better applicability in solving high-dimensional optimization target model.The results of the NSGA-? algorithm for solving the multi-objective optimization location model based on exogenous intrusion risk are compared with the results of the traditional composite monitoring target optimization model.The water coverage rate of conventional water quality monitoring is80% and the monitoring of sudden pollution water quality is carried out.The monitoring failure rate is 30% as the standard meeting requirement.It is found that the former can effectively reduce the expected value of the node monitoring time of the pipe network,thereby improving the overall monitoring efficiency of the water supply pipe network,and proves the monitoring station location obtained by the optimization model based on the external intrusion risk.The program is more scientific and reasonable.Finally,based on the node risk assessment index of the water supply network,the exogenous intrusion probability model of the pipe network is constructed.Combined with the MATLAB software platform equipped with the software EPANET2 dynamiclink library,the intrusion node is selected by the probability model to simulate the pollutant intrusion,and the simulation optimization is constructed.Anti-positioning model.The probabilistic model is incorporated into the genetic algorithm solving system,and the improved algorithm and the basic genetic algorithm are used to solve the simulation optimization-deposition model to obtain the traceability information of the pollutants.Comparing the iterative process,it is found that the convergence rate of the former in the early iteration is about 20% faster than the latter,which proves that the genetic algorithm of the reference probability model has a faster solution speed.