Simplified Procedure to Evaluate Head Losses in Drip Irrigation Laterals

The lateral lines of a drip irrigation system consist of pressurized pipelines with inline or online emitters. Proper hydraulic design of drip laterals usually requires the accurate evaluation of the total head losses, represented by friction losses along the pipe and the emitters, and local losses due to the emitter connections. This paper extends the local loss evaluation procedure, previously obtained for coextruded laterals, on the basis of new experiments. In addition, a simplified procedure was proposed based on the constant outlet discharge assumption for a quick evaluation of total head losses in drip irrigation lines, taking into account the total local loss due to the emitter connections. Total head loss values measured on 15 commercially available coextruded laterals were then compared with those obtained by using the nowly proposed methodology. Relative errors on the pressure head estimation for the examined cases were always ±2.4%, and therefore the proposed methodology could serve for a quick, approximate evaluation of the total head losses along the laterals.