喷微灌输水管网优化设计

以连续管径和水泵扬程为设计变量，以管网年费用最低为目标函数建立非线性规划模型，采用拉格朗日法求解，获得一组最优管径组合；参考第一级优化的连续管径组合，结合施工中要求的变径数选择标准管径组合，以具有标准管径的管长为决策变量，以管道年费用为目标函数，建立相应的线性规划模型，采用单纯形法求解获得全局最优解。通过实例说明，借助于V1sual-Basic语言编制的该设计程序，设计界面友好，使用直观方便，运行速度快，即使非专业人员也可在短时间内进行工程设计，且适用于任何压力输水管网的设计。

The Optimal Design for Sprinkle and Micro Irrigation Main Pipe Net

Sprinkle and micro irrigation main pipe net with pressure was designed by two grades optimalmethod. Annual cost was used as objective function and successive diameter and pressure of pump was used asdecision variation. A nonlinear programming is established and solved by Lagrange method. A series of successiveoptimal diameter are obtained. On the base of the first optimal diameter, some shopping diameters are selectedaccording to the number of diameter variation of operational requirement. The diameter and length are used asdecision variation to obtain minimum annual cost. A linear programming is established and solved byDanChunXing method. Then water pressure of every dot along to main pipe was computed. By using themethod, not only is minimum annual coat obtained, but also is operational requirement satisfied. A designexample is displayed. The result showed that no specialist could use the design program, which is based onVisual-Basic language, conveniently and it is suitable for any pressure main pipe net design.