Parâmetros da pulverização na faixa de distribuição com vant utilizando diferentes tamanhos de gotas

Abstract

This study aimed to determine the spray distribution range using an unmanned aerial vehicle (UAV) with different droplet sizes. The volumetric median diameters (VMD) applied were 100, 200, 300, 400, and 500 μm. The experimental design consisted of randomized blocks with 15 treatments and 3 replications. Treatments were composed of water-sensitive papers spaced 1,0 m apart along a 14,0 m transect, mounted on metal structures at a height of 0,5 m above the ground, used to collect droplet impacts from the spraying. Each water-sensitive paper represented an experimental plot. The UAV used was the DJITM Agras T40, equipped with two rotary spray nozzles (LX8060SZTM), calibrated to apply a spray volume of 10 L ha−1 at a speed of 5,6 m s−1 and a flight altitude of 4,0 m above the target. The experiment was conducted at Seeds Iberá Farm, in Ponta Grossa, Paraná, Brazil. The variables assessed using the DropScopeTM device included: percentage of covered area, recovered volume (L ha−1), droplet density (impacts cm−2), drift potential (percentage of droplets <150 μm), droplet diameters corresponding to 10%, 50%, and 90% of the accumulated volume (DV0,1; DV0,5; and DV0,9 μm), relative span (SPAN), and coefficient of variation of droplet sizes (%). Results showed that covered area, recovered volume, droplet density, and the coefficient of variation increased in the central collection zone, particularly with larger droplet sizes. Drift potential was lowest at the center and highest at the edges. The greatest droplet diameters were observed in the central region. The effective swath ranged from 14,0 to 13,0 m for 100 to 200 μm droplets, and from 13,0 to 12,0 m for droplets above 300 μm. The SPAN values indicated a homogeneous droplet distribution.