Investigation of Water Distribution Characteristics for Large Cannon Irrigation Sprinkler under different Spacing and Layouts

Abstract

Relevant factors affecting the irrigation performance of large cannon sprinkler include the nozzle diameter, operating pressure, layout form, and overlapping distance, which were studied under no wind conditions. The discharge coefficient ranged from 0.96 to 0.99. A mathematical model of radius of throw was regressed and the coefficient of determination was 0.9765. The application rate was lower near the sprinkler, and the highest value occurred under the radius of throw from 4 to 6 m for each water distribution pattern. The average application rate decreased with increase in operating pressure. The average application rate increased with the increase in nozzle diameter. The increased or decreased in magnitude of average application rate under small nozzle diameter was larger than the large nozzle diameter for the same range pressure variations. The maximum CU values increased with increase in pressure under different nozzle diameter or different layouts. Triangular layout gave higher uniformities compared with square layout. The optimal CU values and spacing coefficients of large cannon sprinkler with different layouts, pressure and nozzle diameter were proposed.