Modified $\mathsf{G}$ and ${\mathsf{G}}_{\mathrm{AVG}}$ Correction Factors for Laterals with Multiple Outlets and Outflow

Anwar’s friction correction factor, $G$, and the average correction factor, $G_{\mathrm{AVG}}$, are used to compute the head loss resulting from friction and to calculate the required inlet pressure in horizontal tapered sprinkler laterals with multiple outlets. As a result of their being developed by using a discrete outflow model, which consists of a finite number of operating outlets, the previous approaches for determining these factors required tables or the solving of relatively complex formulas that may be cumbersome. In addition, use of these factors is subject to certain errors when the Darcy-Weisbach equation is used because they are developed assuming a constant friction factor along the lateral. In this study, considering the continuous flow-rate variation concept, at first, two simple and direct equations for calculating the $G$ and the $G_{\mathrm{AVG}}$ factor were developed. The proposed equations are then adjusted for the case in which the variability of the friction factor should be considered. The validity of suggested equations is demonstrated by an example and compared with the accurate numerical solution.