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A newly designed dynamic fluidic sprinkler was tested with different types of nozzles at different operating pressures. Therefore, the aim of this paper was to evaluate the hydraulic performance of a newly designed dynamic fluidic sprinkler. MATLAB R2014a software was employed to establish the computational program for the computed uniformity. Droplet sizes were determined using a Thies Clima Laser Precipitation Monitor. Results showed that the nozzle with a diameter of 5.5 mm gave the highest coefficient of uniformity value of 86% at a low pressure of 150 kPa. The comparison of water distribution profiles for the nozzle sizes (2, 3, 4, 5.5, 6 and 7 mm) at different operating pressures (100, 150, 200, 250 and 300 kPa) showed that a 5.5-mm nozzle size produced a parabola-shaped profile at 150 kPa. The mean droplet diameters for the nozzles sizes of 2, 3, 4, 5.5, 6 and 7 mm ranged from 0 to 4.2, 0 to 3.7, 0 to 3.6, 0 to 3.2, 0 to 0.5 and 0 to 3.8 mm, respectively. The comparison of droplet size distributions showed that 5.5 mm had the optimum droplet diameter of 3.2 mm. The largest droplet sizes had a maximum value of 4.0 for a 2-mm nozzle size. For all the nozzles sizes, 5.5 mm produced better results for hydraulic performance, which can significantly improve the performance and save water for crop production in sprinkler-irrigated fields.

The 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%.