Irrigation Lateral Design
- 160k Downloads
Water is conveyed to drip emitters and sprinklers through multioutlet pipelines called laterals. This chapter begins with a basic introduction to hydraulics and statistics. These introductory materials may be unnecessary for many students. Then these principles are used to simulate the distribution of water applied by an irrigation lateral. Hydraulics is used to determine the change in pressure and resultant application variability along the lateral. Normally, the design objective is high application uniformity, which is accomplished by keeping pressure variation along the lateral within an acceptable range. Using larger pipe reduces pressure loss due to friction, but it also increases capital cost. Irrigation system application uniformity is not only a function of hydraulics. Other causes of nonuniformity include emitter manufacturing variation and application rate nonuniformity. The manufacturer’s coefficient of variation or expected field application variability is used to add a statistical distribution to the hydraulic application rate distribution along the lateral. Monte Carlo analysis utilizes the random number generator in Excel to evaluate the effect of the coefficient of variation on application distribution and profit.
KeywordsSystem design Irrigation hydraulics Optimization Flow variation Uniformity Irrigation laterals
- Heermann DF, Duke HR, Serafim AM, Dawson LJ (1992) Distribution functions to represent center-pivot water distribution. Trans ASAEGoogle Scholar