Study On Stochastic Programming Of Micro-irrigation System

On the basis of analyzing the usual problems in the design of micro-irrigation, network for micro-irrigation is optimize designed. By the method of combining analysing the theories and the engineering examples and of stochastic programming,the network for micro-irrigation is optimize designed,and the stochatic non-linear programming model of micro-irrigation system is built.On the base of analysing the ordinary design methods,aiming to the minimum annual cost or investment, taking the pipe length and water pump lift as decision-making variables, the linear programming models are presented to optimize the diameters of main network and field network. In usual condition , the work system of alternation irrigation is adopted in the micro-irrigation system design. That is the farmers have no choice but to irrigating by turns. And they can't take into account distributing of crops and water requirement and water content of soil. Aiming at the limitations of this irrigation system , a expressions about design flow of pipe networks is set up by the probability methods. A model of stochastic non-linear programming by random irrigating is presented to optimize network of micro-irrigation. And the answer to optimum design of network is analysed about a model of stochastic non -linear programming and FORTRAN program is compiled accordingly . At last, the stochastic model and the linear programming are both applied to optimum design of drip-irrigation project for Jiangsu Province Haimen city Changle town.Then the results are compared and analysed .