Hydraulic performance of the rotational damping sprinkler: Analysis of the force acting on diffuser tooth I

Abstract

Improving water distribution uniformity is crucial for the development of high‐performance irrigation sprinklers, and the diffuser's tooth length greatly influences water distribution. Five diffusers with varying tooth I lengths were designed and researched. The expressions for the force acting on tooth I, the hydraulic performance of the sprinkler and the combination uniformity were obtained analytically and experimentally. The results showed that the tooth I force is affected by the working pressure, the ratio between the plate outlet area and the riser pipe flow area, tooth width, entry water depth, trajectory angle and tooth I slope surface angle. Moreover, the components of the tooth I force acting in the vertical, radial and circumferential directions increase with the tooth I length and working pressure. The necessary condition for normal diffuser operation is that the force in the aforementioned three directions should be greater than 0.37, 0.57 and 0.28 N, respectively. Furthermore, when the working pressure is increased by 50 kPa, hereby reducing the rotation time by 10 min and the tooth I length by 1 mm, its water distribution and combination uniformity are optimal. This study provides a basis for designing and operating diffusers and improving sprinkler hydraulic performance.