IDEAL DESIGN OF LOW-HEAD COILED-TUBE IRRIGATION

Abstract

In low-head tube irrigation, water is applied to the soil surface as a little stream, typically from a small-diameter tube without filtration. The objective of this study were coiling the tube to overcome its lengths problems and developing mathematical model to design the lateral of low-head coiled-tube irrigation with full water application uniformity. Constructing the model include input data under determined operating conditions to get the optimum design. The design model was developed to identify lateral length (Ll), coiled-tube lengths (Cl) and pressure heads (Ch). by using the input data of lateral inside diameter (LID), coiled-tube inside diameter (CID) and discharge (Cq), tube interval distances (Cs), soil surface slope (%), and water temperature (Tw). The optimum design example was presented to three coiled-tube diameters of 3.8, 5.2 and 6.8 mm under upstream low-head pressure (Lh.a) of 0.5, 1.0 and 1.5m for predetermined tube discharges. The results show that the effect of each parameter in the design output.