Pressurized pipelines with multiple outlets (laterals and manifolds) are extensively used to distribute water in irrigated areas under different types of irrigation systems such as surface, sprinkler, and trickle irrigation submain units. Adequate analysis of hydraulic design of multiple outlets pipeline is very important concern for the proper performance of these systems. Hydraulic design of a multiple outlets pipeline is one of the important factors in the ultimate success or failure of irrigation systems. A multiple outlets pipeline is a hydraulic structure whose design is limited by the operating inlet pressure head, and by water application uniformity that is affected by the total energy loss along the pipeline, the field topography, as well as the outlet hydraulic characteristics. This paper will review the fundamental concepts and principles upon which the hydraulics of multi-outlet pipeline systems is based. The paper will conclude the governing equations for steady-state pipe flow that will allow readers to better understand the improved analytical derivations.The proposed methodology is found to be simple, sufficiently accurate, and can be used efficiently for different types of pressure profiles in different line slope situations. It offers considerable flexibility by directly computing values of the required hydraulic variables along the energy profile, incorporating different uniformity patterns and without requiring any additional hydraulic variables, such as pipe diameter, total inlet discharge, required average outflow, downstream end pressure head, total friction drop or outlet hydraulic characteristics.
Anahtar Kelimeler: Steady-state analysis, turbulent flow, friction coefficient, Reynolds number, hydraulic-grade line (HGL), energy-grade line (EGL).
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