This study evaluates the effect of riser heights on the coefficient of uniformity (CU), distribution uniformity (DU), and application rate of spiral fluidic sprinkler (SFS) irrigation systems. The aim is to accommodate taller crops and reduce water losses in an outdoor environment. A field experiment was conducted with four different riser heights (1.2, 1.6, 2.0, and 2.4 m) under two operating pressures (0.25 and 0.30 MPa), using nozzle sizes of 3, 4, and 5 mm to assess their impact on water distribution uniformity and quadrant completion time under varying conditions. The design established 56 catch cans positioned in a four-quadrant arrangement with three radial lines at 1.0 m apart for data collection. ANOVA was conducted on the water retained in the catch cans using Tukey’s honestly significant difference (HSD) method. Tests were then carried out to identify the specific heights that showed significant differences. The F-value of 16.054 (p<0.0001) indicated a significant difference in the responses to different heights. Additionally, the results showed that each increase in height resulted in a decrease in the average application rate. The study concluded that riser heights of 2.0 and 2.4 m provided the best performance for CU and DU, making them suitable for irrigating taller crops while reducing water waste.
Zhu et al. (Fri,) studied this question.