Analysis of Irrigation System by the Unsteady Flow Approach

Abstract

A new method was proposed for hydraulic analysis and designing a multiple outlets such as sprinkler irrigation system. Pressure head H and velocity of the flow V at inlets of each lateral in the system are determined by relationship expressed by function H=f (V) . Supposing that valves are mounted at inlets of each lateral, using unsteady flow approach with downstream boundary conditions at valves identifffied by the above function, values of pressure head and velocity at inlets of each lateral will be rapidly and easily determined. With obtained results, pressure head and discharge of the flow at each sprinkler on each lateral will be also determined by forward step method. A flow chart for calculation on a personal computer was included. Our results show that using this method, we can analyze and design any complex sprinklers, micro-sprinkler and drip irrigation system. In addition, the calculation procedure is simple and results are accurate and fast.