Effects of Longitudinal and Transverse Travel Direction on the Hydraulic Performance of Sprinkler Machines on Sloping Terrain

Background: The influence of varying slope gradients on the hydraulic performance of sprinkler irrigation systems operating on sloping farmland is investigated, with a specific focus on longitudinal and transverse travel directions. Methods: A sprinkler irrigation performance test system for sloping terrain is established, combining theoretical analysis with field experiments. The study systematically examines how different slope conditions affect sprinkler irrigation intensity and uniformity, and identifies the impact of longitudinal and transverse sprinkler machine movement on hydraulic performance under sloping conditions. A three-factor, three-level orthogonal experimental design is adopted, using slope gradient, nozzle pressure, and walking speed as variable factors, with sprinkler irrigation intensity and uniformity as optimization objectives. Results: Results indicate that the influence of slope angle on both sprinkler irrigation intensity and uniformity diminishes along both longitudinal and transverse travel directions. Furthermore, slope gradient exerts the greatest influence on sprinkler irrigation uniformity, followed by walking speed and nozzle pressure. For sprinkler irrigation uniformity, optimal parameters under transverse travel are determined as a 5° slope, 250 kPa pressure, and 30 m/h speed. Under longitudinal travel, optimal sprinkler irrigation uniformity is achieved at a 5° slope, 300 kPa pressure, and 30 m/h speed. Regarding sprinkler irrigation intensity, nozzle pressure and walking speed demonstrate the greatest influence, followed by slope gradient. Optimal intensity for both travel directions is attained at a 5° slope, 300 kPa pressure, and 30 m/h speed. Conclusion: These findings provide theoretical guidance for selecting sprinkler travel patterns and optimizing operational parameters on sloping farmland, offering significant practical implications for enhancing irrigation efficiency and mitigating slope soil erosion.