Research On Simultaneous Optimal Model And Algorithm Of Loop-Type Pipe Network

The irrigation of water-delivery with pipelines is an important way to develop the water-saving agriculture, and its tendency is the pipeline irrigation system. In the whole pipe irrigation network system, the pipe network investment usually contains 50-80% of the total investment. Moreover, water delivery system affects the energy consumption and operational management costs of the pipeline system. Therefore, in the situation of the limited project fund, it has significant meaning to perform the optimal design for reducing the investment, reducing the energy consumption, enhancing the economic and social benefits. The guiding principle of optimal design is to satisfy the water volume and irrigation pressure request, seek the lowest cost or the smallest yearly operation expense and have the highest system reliability.The research is focus on the loop pipe network, based on the summarization of the previous pipe network optimization and the optimized technology achievement. In view of the existing problems and shortcomings, combing theoretical study with analysis of computer and case, this thesis optimize the loop pipe network layout and diameter simultaneous optimization design coding method based on the integer code genetic algorithm, automatically method for identifying water flow route of different pipe layouts, and an automatically calculating program of water pressure of nodes and flow velocity of different pipes, put forward a pipe layout and diameters simultaneous optimization model and algorithm of loop pipe network, combining theoretical study and optimization algorithm with computer analysis and case analysis, adopting Genetic Algorithm(GA) optimization theory. This thesis achieves integration of software and program of pipe network layout and diameter simultaneous optimization design based on the MATLAB integer code genetic algorithm.This thesis mainly achieved the following results:(1) Using a continuous Hopfield neural network clustering algorithm to solve loop pipe network layout problem and optimized the allocation of water supply looped network design.(2) Using Genetic Algorithm for Pipe Network Hydraulic Calculation and Optimal Design of Synchronous diameter selection. Solution of the model is not dependent on the problem itself but from the global space search problem the optimal solution. Application of research methods used integer encoding, to avoid redundant genetic coding of binary problems.(3) This section of code in the layout design based on the experience of the designer and determines the flow of each pipe diameter range and choice of design experience into organic optimization of the initial stage. The code design method can effective in reducing the number of infeasible solutions and improve the computational efficiency of optimization and feasibility.(4) Solve the optimization of the network layout, ring diameter hydraulic calculation and optimization of the network to achieve global optimization. Reducing investment has significant meaning. This thesis also enrich network design theory.