IWRA Proceedings

Microirrigation systems are methods of applying water, nutrients and chemicals directly to the plant root area at a controllable rate, which allows maximum results and minimum use of water and energy. For these reasons, microirrigation systems are developed in arid countries with insufficiency in water resources. They have expanded to many countries engaging in modern agricultural practices due to relatively high agricultural outputs and low energy expenses. For microirrigation to be profitable, system design’s must be based on precise calculations and rigorous management. The precision with which microirrigation lateral and network's are designed is of fundamental importance to system operation, the uniformity of distribution of water and fertilizer, and the consumption of energy. The computation model presented in this paper is based on equations of mass and energy conservation within an elemental control volume on the lateral. Considering the variation of the out-flow regime leads to an algebraic, coupled and non linear equations system whose resolution is based on the numeric methods to a defective analytic approach. In this work, the control volume method was selected due to its simplicity. A program of computation has been developed for this and applied to a lateral for the first time . Results from this simple model are precise and are similar to those from other validated models. Precision design increase efficiency of water and fertilizer distribution. This method can be applied to the design of microirrigation lateral's or network's.