Friction Coefficient for Center Pivot Systems

An important objective of any center pivot irrigation system is to achieve a uniform distribution of water delivered through the sprinklers. In this study friction coefficients are developed for designing center pivot irrigation systems using two of the most common methods used for estimating friction head loss in sprinkler irrigation pipelines. A center pivot system operating under field conditions was used to verify the analysis. In the analysis, the change of sprinkler discharges along the lateral affects the Reynolds number and hence the state of flow along the lateral has been taken into account. The calculation of friction coefficients and friction head losses from the two equations are compared with the field data