Abstract:Data logging rain gauges and two-dimensional video disdrometer (2DVD) were applied to measure its water application rate, droplet diameter and velocity in radial direction of Nelson D3000 blue spray plate sprinkler with 4.76mm nozzle. The equations of peak application, peak kinetic energy rate about working pressure and mounting height were regressed based on the diffusion of water application and kinetic energy under different working conditions. The result indicates that the diffusion of water application rate and droplet kinetic energy are facilitated by increasing the working pressure and mounting height. This is due to that the jet flow speed is higher when the operating pressure increased, and with the air turbulence enhanced, it is easy to smash. The water drops to pieces. At the same time, the duration of landing increased when the mounting height is high. That seems to have the same effect. The low nozzle height which presents high peak application and kinetic energy rate leads to the generation of runoff. The peak water application and droplet kinetic energy rate varied from 166.4mm/h to 196.4mm/h, and 0.607W/m2 to 0.821W/m2 , respectively. The equation of peak rate can be helpful to design the working pressure and mounting height in sprinkler systems to prevent high peak application rate and kinetic energy rate which leading to occurrence of runoff.