A procedure is described to determine and evaluate radial water distribution profiles for a sprinkler head operating at conditions intermediate to those of the tests. Forty water distribution profiles from a PLONA-RL250 sprinkler, obtained under different combinations of 8 nozzle diameters and 5 working pressures, were used. Profiles determined under pressures of 294, 490, 686 kPa were used to generate profiles for 392 and 588 kPa pressures. Profiles determined for 14 x 6, 18 x 6, 22 x 6 and 26 x 6 mm nozzle diameters were used to reproduce radial profiles for 16 x 6, 20 x 6 and 24 x 6 mm nozzle diameters. The radial profiles generated for working pressure and nozzle diameters, compared to the radial profiles observed, respectively, had mean values of: i) determination coefficient of 0.921 and 0.921; ii) coefficient of variation of 9.5 and 9.4%; iii) probability (Student t test) of 88.5 and 87.3%. Computer simulations of water application uniformity from radial profiles observed and generated for working pressure and nozzle diameters presented, respectively, mean absolute deviation of 1.36 and 1.44%. The procedure proposed does not influence significantly the values of water application uniformity.
irrigation uniformity; nozzle size; working pressure
