Study On Optimal Design Of Scale Pipe Irrigation Network System

With the water shortages and the intensification of contradiction between supply and demand, Water has become a strategic resource for economic and social development.It is one of the substances essential to industrial and agricultural production.Relative lack of water resource in our country. Per capita water resource was less. Agriculture accounts for a large proportion of the country’s water. Improving the utilization of water in agriculture is an effective way to save water. Pipeline irrigation with a smaller footprint, lower leakage and evaporation is widely regarded as an important measure of water-saving irrigation. In recent years, with the pipeline irrigation pipe network control area increases, how to ensure the lowest cost in the economic situation of Flow equalization and safety regulation is the key issue to be resolved pipe network optimization.This article is based on previous studies, through the literature analysis, summarized the pipeline irrigation pipe network optimization design method research status. Established pumping tree irrigation pipe network optimization model under suitable conditions of pressure, And using of genetic algorithm and LINGO software for solving optimization model, the main research results are as follows:(1) Analysis of the cost to construct a tree irrigation pipe network and constraints in the pipeline investment costs, annual operating costs as the target pump function, an orifice flow balancing,bearing pressure pipelines, pressure head node, standard diameter, pipe length as an optimization constraint, Established a pumping station under pressurized conditions nonlinear tree pipe network optimization model.(2) Contraposing large-scale nonlinear programming model has many variables, complex constrints,using conventional methods to obtain the optimal solution of the problem is difficult.This paper introduce genetic algorithm based on MATLAB to solve this model.Genetic algorithm has strong global optimization ability in dealing with such discrete variables, To quickly converge the optimal solution and short time running, For instance in genetic programming algorithm, using a genetic algorithm based on MATLAB toolbox(GATBX), integer encoding to program design, reduce the length of chromosome, to avoid redundant coding problem. Constraints on treatment using the objective function was added in the form of penalty function, by setting the appropriate penalty coefficientand genetic design parameters obtained tree pipe network optimization model of the optimal solution.(3) Using the LINGO software applications to solve the optimization model, the using of general-purpose programming language LINGO, strong timeliness, writing programming in LINGO11.0 platform, the genetic algorithm and LINGO solution results were compared and analyzed.(4) The optimization model validation in the irrigation district, the standard diameter pipe network may be used in the least squares fit to re-group rotation irrigation pipe network to be divided, combined with the terrain data, putting relevant parameters into the optimization model, compared the effects of different genetic algebra maximum optimization results, and optimizing the economic results of the original design.The program flow technique were compared to verify the feasibility of the model,It can play a role in large-scale tree irrigation pipe network pressure equalization control.