Click on “Download PDF” for the PDF version or on the title for the HTML version.

If you are not an ASABE member or if your employer has not arranged for access to the full-text, Click here for options.

Abstract. We built a model to simulate how the stop-go movement of a center pivot or linear move irrigation system affects the overall irrigation system‘s distribution uniformity. We modeled rectangular, triangular, elliptical, and donut sprinkler patterns and the overlap that is formed from the stop-go movements. We found that the uniformity results could be reduced to looking at the move distance of the pivot as a percent of the wetted radius. Setting the move distance to be roughly equivalent to the wetted radius resulted in the most consistently good uniformity results for the most common sprinkler application patterns. Setting the run time of the last tower as a constant, such that the move distance is equivalent to the sprinkler wetted radius, can improve uniformity for high percent settings, and can drastically reduce the number of start-and-stop cycles of drive motors and gear boxes for lower speed (% timer) settings, lengthening the life of these components. The pivot percent setting, or application depth can then be controlled by varying the cycle time (time between motor starts).