Effect of riser height on rotation uniformity and application rate of the dynamic fluidic sprinkler

Abstract

AbstractThe objective of this paper was to investigate the effect of riser heights on rotation uniformity and application rate of the newly designed dynamic fluidic sprinkler. The dynamic fluidic sprinkler was tested using different nozzle sizes of 5 and 6 mm. The sprinkler head was mounted on 1.3, 1.5, 1.7 and 1.9 m risers at 90° in the horizontal direction and was placed about 0.9 m above the top of the cans. The following operating pressures were tested: 150 and 200 kPa. A program was written to simulate the non‐uniform of rotation of the nozzle during the full circle‐spraying process. It was found that the riser height had a significant effect on application rate and uniformity. The comparison of standard deviation with different risers showed that differences in standard deviation were much lower for the 1.9 m riser height. The deviation was in the range of 0.14 ~ 0.26, 0.14 ~ 0.42, 0.18 ~ 0.50 and 0.13 ~ 0.69 mm h−1 considering the riser heights of 1.9, 1.7, 1.5 and 1.3 m. For all the nozzle sizes, a smaller standard deviation was recorded under 150 kPa. The deviation range was 0.15 ~ 0.24, 0.17 ~ 0.45, 0.18 ~ 0.45 and 0.2 ~ 0.66 mm h−1 for 1.9, 1.7, 1.5 and 1.3 m, respectively. With respect to nozzle sizes, 5 mm gave better standard deviations and the deviation range was from 0.14 ~ 0.26, 0.15 ~ 0.45, 0.2 ~ 0.7 and 0.23 ~ 0.74 mm h−1 with radial heights of 1.9, 1.7, 1.5 and 1.3 m, respectively. The range of the coefficient of uniformity values for overlapped quadrants for the 5 mm nozzle was as follows: 78% at a spacing of 10 to 72% at 80% overlapped spacing. The highest occurred at 50% spacing and increased with an overlapped spacing of 10 to 50%, ranging from 78 to 87% with an average of 82.5%. © 2020 John Wiley & Sons, Ltd.