Analysis of kinetic energy distribution of big gun sprinkler applied to continuous moving hose-drawn traveler

Kinetic energy of droplets from big gun sprinklers relates closely to the infiltration process and soil erosion, as well as severely affects the energy consumption of hose-drawn travelers. However, research work related to the kinetic energy distribution of big gun sprinklers is seldom performed. In this study, The radial water application distribution, droplet size distribution, and droplet velocity distribution of a big gun sprinkler were measured. Based on the experimental data, a calculation method was developed to determine the kinetic energy of big gun sprinkler under stationary and moving states. Volume weighted mean particle size and the corresponding equivalent landing velocity were adopted as the feature size and velocity of the point located at any distance from the sprinkler. The droplets' landing velocities present a logarithmic relationship with droplet size and velocities rise with the increase of droplet size. The operating pressure should not be lower than 0.2 MPa since the peak value of specific power will rise rapidly below this operating pressure. For positions receiving the same kinetic energy, obvious difference may exist in the amount of water and the dynamic process curves of specific power. With the increase in travel speed of the hose-drawn traveler, both the cumulative kinetic energy and the irrigation duration decrease proportionally. Compared to the spray plate sprinklers applied to center pivots, the big gun sprinkler shows a milder precipitation process, but the water application lasts longer and carries more kinetic energy, reaching 2- 4 times for the same amount of water. The infiltration rate of each location decreases linearly along with an increase in distance to the travel lane, and the infiltration rate decreases to approximately 20 mm/h at the end of the spraying area.