【作者】 李海滨；

【导师】 马孝义；

【作者基本信息】 西北农林科技大学 ， 农业水土工程， 2009， 硕士

【摘要】 管道输水灌溉是发展节水农业的重要途径,灌溉管道化是灌溉节水发展的趋势。在管道灌溉系统中,管网部分的投资一般要占到工程总投资的50%~80%,而且影响管道系统的能耗和运行管理费用。因此,在工程资金投入有限的情况下,进行管网系统的优化设计、寻求能满足水量和水压要求,且能使整个系统的造价最低或年费用最小、系统可靠性最高的设计方案,对节约投资、降低能耗、提高经济效益和社会效益有着重要的现实意义。本文以树状灌溉管网为研究对象,在总结国内外管网优化研究和最优化技术成果的基础上,针对目前研究中存在的问题与不足,采取理论研究、计算机模拟计算和实例分析相结合的方法,应用遗传算法最优化理论和图论知识,以投资最小为目标,对树状管网布置与管径同步优化遗传算法整数编码方法和不同管网布置下水流路径自动识别和压力、流速等约束条件自动计算方法进行了研究,建立了基于整数遗传算法的树状管网布置与管径同步优化模型。研究了基于Visual Basic6.0开发平台的树状灌溉管网同步优化应用软件,实现了基于MATLAB的遗传算法管网布置与管径的同步优化程序和软件的集成一体化及CAD图形的同步可视化。本文的研究主要取得了以下成果:(1)本文所研究的树状管网同步优化方法主要针对农田中的不规则灌溉管网,依据树状供水管网单点供水的原则,在管网布置段编码设计中,将管网概化为有向网络图,摒弃了图论中遗传计算复杂编码方法,通过简单的编码方法,提高了遗传计算效率,增强优化方法的可操作性。(2)本文在布置段编码设计中,根据设计人员的经验确定出每个节点所有可能的供水管段,将设计经验有机的融入到优化计算的初始阶段,同时也有效地减少了优化计算中不可行解的数目,提高了优化计算的计算效率和可行性。(3)将融入设计员经验的管网布置优化与管径优化结合起来,实现管网的布置与管径的同步优化,以实现管网的全局最优化。(4)利用Sheffield大学开发的gatbx遗传算法工具箱,以MATLAB作为编程工具,在遗传算法程序设计中,采用了整数编码的方法,避免了二进制遗传编码冗余问题。以VB为平台编写的优化应用软件实现了同步优化算法程序和软件的集成一体化及CAD图形的同步可视化。更多还原

【Abstract】 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 generally occupies 50-80% of the total project, moreover, it affects the energy consumption and operational management costs of the pipeline system. Therefore, in the situation of the limited project fund, it has practical significance to perform the optimal design for saving 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 object is tree pipe network. Based on the summarization of the domestic and foreign 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 paper studies the tree irrigation pipe network layout and diameter simultaneous optimization design coding method based on the integer code genetic algorithm, automatical 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 tree pipe network, combining theoretical study and optimization algorithm with computer analysis and case analysis, adopting Genetic Algorithm(GA) optimization theory and Graph Theory(GT). This paper develops a simultaneous optimal design application software based on Visual Basic 6.0 development platform, achieve integration of software and program of pipe network layout and diameter simultaneous optimization design based on the MATLAB integer code genetic algorithm as well as CAD graphics simultaneous visualization.This paper mainly achieved the following results:(1) This paper studies tree pipe network focused on the farmland irregular irrigation pipe network. The model eliminated the redundant links so that each node is supplied only by one single link. In the course of pipe network layout coding design, the pipe network is simplified as a directed network graph, which rejects the complexity coding method in GT. A simple coding method is introduced, that improves the calculation efficiency of GA, and enhances the operation of optimization method.(2) According to the design experience in the course of pipe network layout coding design, this paper determines all the possible water supply pipes of each node. Meanwhile, the design experience is organically applied in the beginning of the optimization method, which reduces the number of infeasible solutions and enhances the calculation efficiency and feasibility.(3) Combining the pipe diameters optimization with the pipe layout optimization syncretizing design experience, realize the pipe layout and diameters simultaneous optimization, so as to achievethe overall network optimization.(4) Using the Genetic Algorithm Toolbox which Sheffield University programmed, this paper applies the integer coding method in Genetic Algorithm programming and avoids redundant problems of binary coding with the help of MATLAB. The application software based on Visual Basic 6.0 development platform achieves integration of software and program of simultaneous optimization as well as CAD graphics simultaneous visualization.更多还原