Field evaluation of an air-assisted sprayer equipped with two reversed rotation fans.

An air-assisted sprayer equipped with two reversed rotation fans was evaluated in a peach orchard. The effects on the spray deposition of the forward speed, the air volumetric flow rate, and the number of activated fans were analyzed. Spray mixtures contained manganese chelate as a tracer. Spray deposition was evaluated qualitatively through visual estimation of water-sensitive papers and quantitatively by analysis of filter papers using an atomic absorption spectrometer. Deposition and canopy penetration increased when the air volumetric flow was increased for most of the sampling points. The forward speed had no significant effect on the deposition and canopy penetration for most of the sampling points. The effect of the number of activated fans on the spray deposition was significant with increased deposition for the case of two activated fans.