This study aimed to evaluate the distribution profile and droplet spectra of low drift spray nozzles TTI110015, AI110015 and AI11001 under different operational conditions. The volumetric distribution was determined on a test table (patternator), by analyzing the coefficient of variation (CV) of a computer simulated spraying boom at pressures 200, 300 and 400 kPa, height of 30, 40 and 50 cm in relation to the patternator and nozzle spacing from 40 to 100 cm. Volumetric Median Diameter (VMD), span (A.R.) and percentage of droplets below 100 µm (% 100 µm) diameter, at pressures 200, 300 and 400 kPa were evaluated. Nozzles were adequate at pressure 200 kPa only for band application and at pressures 300 and 400 kPa only for total area application. Satisfactory CV (under 7%) was obtained, when highest pressure and lowest space between nozzles were applied. Droplet size (VMD) was reduced as pressure was increased. Nozzles TTI110015 and AI11015 at all pressures and nozzle AVI11001, at 200 kPa, presented extra coarse droplets and coarse droplets with AVI11001 at pressures 300 and 400 kPa. Nozzles AI and TTI presented more uniform droplet size at the highest pressure than nozzle AVI, considering the span value. Nozzles presented a low percentage of droplets below % 100 µm, especially nozzles TTI110015 and AI110015, with reduced drift risk.
air induction nozzle; spraying boom; application technology; drift
