Non-negligible factors in low-pressure sprinkler irrigation: droplet impact angle and shear stress

Droplet shear stress is considered as an important indicator that reflects soil erosion in sprinkler irrigation more accurately than kinetic energy, and the effect of droplet impact angle on cannot be ignored. In this study, radial distribution angles, velocities, stresses were investigated using a two-dimensional video disdrometer with three types low-pressure (Nelson D3000, R3000, Komet KPT) under two operating pressures (103 138 kPa) nozzle diameters (3.97, 5.95, 7.94 mm). Furthermore, relationships among these characteristical parameters analyzed, their influencing factors comprehensively evaluated. For various sprinkler, pressures, diameters, smaller angles larger velocities droplets found to occur closer resulting relatively low stresses. The increase distance from caused decrease velocity increase, which contributed significant reached peak value at end jet. Therefore, jet was most prone direction, could not only attributed but also needed combined analysis its stress. Through comparing distributions average sprinklers, D3000 exhibited largest (26.94–3313.51 N/m2), followed by R3000 (33.34–2650.80 KPT (16.15–2485.69 N/m2). From perspective minimizing risk erosion, suitable for sprinklers. addition selecting appropriate type reduce stress, spacing provide acceptable results, because highly (P<0.01) This study results new reference design system.