Solid-set sprinklers irrigation of field boundaries: experiments and modeling

Abstract

Numerous studies have analyzed the solid-set sprinkler irrigation system performance. However, the effect of field-boundaries irrigation has not been considered in the whole-field performance. The objectives of this study were (1) to characterize two different solutions to irrigate field boundaries (full-circle sprinkler equipped with a deflecting plate, DP, and partial-circle sprinklers, PC); (2) to calibrate and validate a ballistic model to adequately simulate these solutions; and (3) to analyze the two different designs (DP or PC) from a whole-field perspective. Two types of experiments were designed. The first was carried out with an isolated sprinkler under no windy conditions to estimate drop size distribution parameters. The second was performed in a solid-set sprinkler layout under windy conditions to calibrate and validate the ballistic model. The experimental design allows the comparison of both solutions under equal technical and meteorological conditions. Comparisons between designs (DP or PC) were established for a whole-field area in terms of irrigation performance and crop yield. From a technical point of view, PC sprinklers perform better than DP sprinklers. From an economical point of view, the shape and orientation of the plot and the legal requirements of the irrigation system design (minimum distance of the sprinkler line to the border) have an important effect on the optimal solution to irrigate field boundaries.