Research on Adaptive Particle Swarms Algorithm for the Optimization of Urban Water Network
|Keywords||optimal design of water distribution system multi-objective model AFIPSO hydraulic calculation BFGS-method|
Urban water supply network, the bridge to connect water supply plant toconsumers, is key point in the city water supply system, accounts for30%-50%of thewater supply energy consumption as well as50%-80%of the investment. As thedevelopment of the urbanization process together with water scarcity, it requires us toraise the water resources utilization, and make more scientific and reasonable plan forurban water supply network, also raise operation management, which will directlyinfluence the project investment and operation management cost.The traditional network optimization model only considers the economy, whichmeans to get the minimum cost for pipe laying under the hydraulic conditions. Thispaper will integrate reliability and economical targets into multi-objective function,reliability is to ensure that the water amount and water pressure is enough forconsumers under the normal working condition, when accident it also can supply waterno less than the specified limit, reliability is defined respectively as nodal available flowand pipe network resilience, the big result of nodal available flow represents moreprobability to get required water and water press under limited conditions, and the bigresult of pipe network resilience means more probability to get water when accident.The total cost of the network is used as the economic function, in the case of conditionfor hydraulic conditions, to get the optimal layout of pipeline network.When inputting pipe information data, pipeline network information is transferredinto the matrix form, and the compression coefficient of numerical matrix method isused to calculate the data, this method effectively reduces the amount of numericalinput, avoids the memory leak, and enhances the input speed.BFGS of Newton method is used for hydraulic calculation, because Newtonmethod is suitable for large-scale nonlinear equation with computer to solve, but thedeficiency of the Newton method convergence limitations, and BFGS method isimproved to overcome the disadvantages of the Standard Newton method, it can getglobal optimal solution with large nonlinear equation.Adaptive particle swarm algorithm (AFIPSO) is used for the optimization designof the network to solve the optimal diameter combination, AFIPSO adjust flight timeand the inertia weights, and makes full use of the objective function to share thenecessary information between particles. AFIPSO overcomes declining search in late evolution of the standard particle swarm, and improves the algorithm stability andconvergence speed. Design And the optimization of pipeline network, finally Matlab isused for programming application.