The effect of different trajectory angles of a gun sprinkler associated with different nozzle diameters and working pressures on the radius of throw and water distribution profile were assessed in this study. The technical characterization of the gun sprinkler was carried out at a sprinkler test bench of the Universidade Federal de Lavras, at Lavras, MG, for 24 different working conditions. In function of nozzle diameter (18 and 22 mm), service pressure (294, 392, 490 and 588 kPa) and trajectory angle (16, 22 and 28º), a potential equation was adjusted to estimate the radius of throw. Furthermore, along the radius of throw the percentage distribution of the amount of water applied was analysed. For low working pressures associated with trajectory angle of 16º, higher reductions were observed on the radius of throw; from the 28º trajectory angle, for every 3º drop of the trajectory angle the radius of throw is reduced by approximately 3.4 to 4.0%; for trajectory angles higher than 22º associated with working pressures higher than 392 kPa, the amount of water applied from the gun sprinkler is more between 60 and 80% of radius of throw.
nozzle diameter; working pressure; radial profile
