Minor Losses and Best Manifold Position in the Optimal Design of Paired Sloped Drip Laterals

Arranging paired laterals so that two distribution pipes extend in opposite directions from a common manifold contributes to providing more uniform pressure to all laterals in the system, increasing water use and energy efficiency of micro-irrigation. Towards this end, by neglecting emitters’ minor losses, analytical procedures to design paired drip laterals laid on uniform slopes were introduced. More recently, it was shown that for an optimal paired sloped lateral design the best position of the manifold (BMP) equals 24%. In this paper, first the mentioned analytical procedure is extended to the case in which minor losses are considered. Second, by neglecting minor losses, a comparison in terms of energy saving, between designing paired sloped drip laterals by fixing BMP = 0.24 and other suggested manifold position from the literature, is performed. Third, it is shown that fixing BMP = 24% of the optimal lateral length can be also applied when minor losses are taken into account. By considering the minor losses of integrated emitters, some practical solutions are presented. The procedure proposed here was compared with that derived by the step-by-step exact procedure. Applications by considering different design variables are performed and discussed. © 2018 John Wiley & Sons, Ltd.