Hydraulic Design of Micro-Irrigation Subunit Based on Genetic Algorithm

With the difference between average discharge and design discharge of emitter to be the objective function, a based-genetic-algorithm model for micro-irrigation subunit hydraulic design is established, which takes the node pressure in the submain end as a decision variable and applies bisection algorithms and back step method to handle the hydraulic calculation of submain and laterals. Simulation results show that the model and algorithm possess excellent solving efficiency, accuracy, and good versatility and practical value. In the meanwhile, it can be also obtained that discharge and pressure distribution of submain and laterals some characteristic value and their orifice location such as average discharge, maximum discharge and minimum discharge of emitter, determine pressure variation, discharge variation, uniformity and other indicators. This model can be applied to hydraulic analysis and design of the micro-irrigation subunit with non-uniform slope, varied-diameter, varied-spacing and so on, and also used to check or evaluate the micro-irrigation subunit which has been designed or completed.