Pulverização com assistência a ar em condições desfavoráveis de vento ambiente

Abstract

The volumetric distribution profile is a decisive factor in selecting a spray nozzle for efficient application of plant protection products with minimal environmental contamination and costs to the producer. This study aimed to analyze the volumetric distribution of a hydraulic flat fan spray nozzle 11002, subjected to air assistance in the presence of ambient wind, under different working pressures, in a controlled environment. Using a tractor sprayer with air assistance in the boom, the volumetric distribution was determined using a patternator, combining two ambient wind speeds (0 and 3.33 m s-1), three working pressures (137.9, 379,2, 620.5 kPa), and three assistant wind speeds (0, 3.75, and 7.25 ± 0,5 m s-1). The experimental design was completely randomized, in a three-factor scheme with three replications, totaling 54 experimental units. From the individual spray nozzle distribution pattern, the overlap was simulated, and the coefficient of variation (CV%) was calculated. The uniformity of the volumetric distribution was estimated by the resulting CV from the simulation. Subsequently, the data were analyzed and interpreted using the sisvar software, applying ANOVA. In cases of significant differences between the means of the treatments, the Tukey test was applied. Air assistance in the boom showed potential to improve spray nozzle application at pressures of 379,2 and 620,5 kPa, even in the presence of ambient wind not recommended for spraying, while maintaining the coefficient of variation below the 10% recommended by NBR ISO 16122-2. Keywords: Application technology; vortex; drift.