Effect of terrain slope on water distribution and application uniformity for sprinkler irrigation

Abstract

Abstract:In order to provide practical parameters for sprinkler irrigation system design on slope land, the effects of terrain slope on water distribution, sprinkler throw radius and water application uniformity were analyzed for the Rainbird LF1200 sprinkler. The results show that, the water distribution curve is roughly "heart-shape" on slope land, and the water has the trend of focusing on the upslope with the increase of the slope. Throw radius decreases for the upslope and increases for the downslope as the slope increases. For the convenience of sprinkler irrigation system design on slope land, a formula for computing throw radius on slope land was put forward by the theoretical derivation, and it was verified by the experimental data. The impact of sprinkler pressure and spacing on CU for slope land is more significant than that for flat ground. Under the experimental condition, no significant change is found regarding the influence of terrain slope on water application uniformity at the confidence level of 95%. Taking irrigation quality and economy into account, the Rainbird LF1200 sprinkler should be operated at the manufactures' recommended pressure, rather than low pressure, with sprinkler spacing from 8 m×8 m to 10 m×10 m below the slope of 0.15 in practice.

Comprehensively evaluating and modelling droplet diameters and kinetic energies of low‐pressure sprinklers

“…With further increase in distance from the sprinkler, the distribution ranges of droplet diameters and volumes continued to expand and reached a maximum at the end of the spray jet. This also implied that the distributions of droplet diameters and volumes were very discrete at the end of the low-pressure sprinkler jet, which might be the most dynamic area of the entire jet trajectory and droplet break-up and collisions (Zhang et al, 2018).…”

Development in sprinkler irrigation technology in China*

“…The sprinklers, risers and some movable pipes in the field will hamper the operation of agricultural machinery, so some sprinkler irrigation devices have been specially protected. Full use was made of the gravity head of hills for gravity sprinkler irrigation, which promoted the development of special equipment for sprinkler irrigation in hilly sloping land and related technology research (Chen, 2011; Zhang et al, 2018a). Since the 1990s, with the rapid development of the plastics industry, underground and permanent pipes in China have been mainly made of PVC and PE (Bai and Xie, 2018), and movable lateral pipes were mainly made of aluminium alloy pipes and plastic‐coated hoses (belts).…”

The Influence of Sinusoidal Oscillating Water Flow on Sprinkler and Impact Kinetic Energy Intensities of Laterally-Moving Sprinkler Irrigation Systems

“…The Christiansen uniformity coefficient (Cu) is a commonly used indicator in sprinkler irrigation water application uniformity assessment [31]. After obtaining the combined distribution data of sprinkler intensity and impact kinetic energy intensity, the Cu of sprinkler intensity and impact kinetic energy intensity is calculated using Equations (2) and (3).…”