Comparison of Fixed and Rotating Spray Plate Sprinklers

Abstract

A comparative study of two types of spray sprinklers was performed. Rotating spray plate sprinklers (RSPSs) and fixed spray plate sprinklers (FSPSs) were evaluated individually in open field conditions. The water distribution, wind drift, and evaporation losses during the evaluations were measured under low, medium, and high wind speed conditions with three nozzle diameters and two nozzle heights above the soil surface. Individual spray sprinkler water distributions were mathematically overlapped to simulate the water distribution resulting from sprinkler machines. The water distribution of the RSPS had a conical shape, whereas the FSPS concentrated the water application in a circular crown. The uniformity coefficient of the simulated water application in sprinkler machines fitted with RSPSs or FSPSs was >93% in all cases. However, the RSPS could attain a higher uniformity coefficient at higher spacing along the lateral. For the nozzle diameters of 6.7 and 7.9 mm, the wetted width produced by the RSPS was larger than that of the FSPS. Also, the peak instantaneous precipitation rate of the RSPS was smaller than that of the FSPS.