Multi Objective Optimization Of Rural Water Supply Network Considering Uncertainty And LCCA

Rural water supply project is an important infrastructure in rural areas and one of the important construction contents of Rural Revitalization.The implementation of centralized water supply in rural areas is of great significance to improve the rural living environment and conditions,improve the level of rural water supply security,and promote the centralized management and unified distribution of water resources.After the implementation of the task of poverty alleviation in China,great achievements have been made in the construction of rural water supply projects,but there is still room for improvement in the popularization rate of tap water,water supply quality,efficiency,engineering design and management level.Due to financial constraints,it often focuses on reducing the initial investment,fails to take into account the performance and cost of the whole life cycle of the project,and some projects underestimate the change of water demand,which affects the later water supply safety and quality.Based on the idea of project life cycle cost optimization design,considering the uncertainty of some parameters in the water supply system,this paper studies the optimization design of rural water supply system.The node flow and pipe friction coefficient(Hazen Williams coefficient)are considered as random variables.At the same time,according to the life cycle cost analysis theory,the optimization model of rural water supply network is established,Determine the arrangement and combination of pipe diameter in each pipe section of pipe network,and NSGA-Ⅱ algorithm is used to solve the optimization model of rural water supply network(1)Combined with the research status of optimization design of rural water supply network at home and abroad,supervisor analyzes the necessity that the optimization design of rural water supply network should consider the randomness of network parameters and network economy,and should be based on the life cycle cost analysis theory.(2)Based on the life cycle cost analysis theory,the initial construction cost,operation cost and depreciation overhaul cost of water supply network are analyzed quantitatively,and the life cycle cost model of water supply network is established.(3)The node flow and pipeline friction coefficient(hazenweigh coefficient)are regarded as random variables,and the random distribution model of node flow and hazenweigh coefficient is established.Considering the random distribution model of node flow and hazenweigh coefficient,the optimization model of water supply network is established under different confidence.The optimization model is solved and the results are compared and analyzed.(4)An optimization model with the minimum total cost and the minimum average node head margin in the whole life cycle of the pipe network as the objective function and the pipe diameter as the decision variable is established.The multi-objective optimization model of multi water supply network is solved by NSGA-Ⅱ algorithm.The feasibility of the optimization model of the pipe network and the solution of the optimization model by NSGA-Ⅱ algorithm is verified by an engineering example.The results show that the reliability of water supply is higher and more in line with the actual situation considering the uncertainty and the life cycle cost model,which can provide important decision support for the selection of the scheme in the design stage of the water supply system.At the same time,the feasibility of multi-objective optimization design of rural water supply network considering uncertainty and LCCA and the application of nsgaⅡ algorithm to solve the optimization model are verified.