Ingénierie des systèmes d’irrigation et de drainage

A Software for Hydraulic Analysis of Linear-move and Center-Pivot Irrigation Systems: LincSys, II. Application Examples and Model Evaluation

Abstract

Zerihun D and Sanchez C.A.

A software for simulating the hydraulics of linear-move and center-pivot irrigation systems, LincSys, is presented in the current paper. This manuscript is part II of a two-part paper. Descriptions of software functionalities relating to the graphical user interface and the hydraulic simulation module of LincSys are presented in manuscript I. Results of evaluation of the computational module are summarized and a set of application examples are presented here. A limited evaluation of the hydraulic simulation module suggests that the predictive capability of the model is satisfactory. In line with results of earlier studies, computed outputs of application examples show that the lateral pressure profiles of linear-move and center-pivot systems exhibit both local span-scale spatial variability patterns and broader inter-span trends, suggesting that a complete description of the pressure profile patterns of these laterals requires that both spatial variability attributes be assessed. While the lateral pressure spatial variability properties are primarily functions of span geometry, the outcomes of the current study confirm results from an earlier study that field slope and lateral diameter can modify the basic effects produced by span geometry. Simulated emitter discharge profiles indicate that distribution uniformity along linear-move and center-pivot laterals can be high. The results also show that, depending on the system configuration option, the spatial variability attributes of an emitter discharge profile can have similarity with certain aspects of (or can be completely different from) that of the corresponding lateral pressure profile.