Submitted to: Journal of Irrigation and Drainage Engineering
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/25/2019
Publication Date: 7/2/2019
Citation: Zerihun, Z., Sanchez, C.A., Thorp, K.R., Hagler, M.J. 2019. Hydraulics of linear-move sprinkler irrigation systems, III: Model evaluation. Journal of Irrigation and Drainage Engineering. 8(2):1-11.
Interpretive Summary: Improving the efficiency of water use for agricultural production requires knowledge of the hydraulic performance of irrigation machines, such that their operation can be optimized. Toward this end, scientists build hydraulic models that describe pressure and flow at different points in the irrigation system. These models must be evaluated against measured data from irrigation machines. In this research, detailed pressure and flow data were collected during the operation of an overhead lateral-move irrigation machine, and these data were used to evaluate a hydraulic model of the irrigation machine performance. The model will assist researchers, growers, and the irrigation industry to optimize the performance of irrigation machines, thereby gaining efficiency in water use for agricultural production.
Technical Abstract: A hydraulic simulation model of linear-move sprinkler irrigation system, equipped with pressure reducing valves (prvs), is presented in the companion paper. Results of model evaluation and simulation examples, showing model applications, are described here. Measured hydraulic data-sets, consisting of lateral pressure head profiles and inlet discharges, were used in model evaluation. The data was obtained through field tests conducted on a linear-move sprinkler irrigation system fitted with prvs. Comparisons of model-predicted and field-measured lateral pressure head profiles and lateral inlet discharges suggest that model performance is satisfactory. Furthermore, potential applications of the model in analyzing prv-set pressure effects on lateral hydraulics and, possibly, in the selection of a suitable prv-set pressure for a lateral with a given parameter combination are shown using simulation examples.