Numerical Simulation of the Air-Assisted Boom Spraying and Droplets Transporting Process

Abstract

The conflict between increasing the deposition on target and reducing off-target losses in conventional pesticide spraying is an issue. It has been confirmed that air-assisted spraying can effectively reduce the drift compared to the conventional spraying. The work presented here reports on the numerical simulation of an air-assisted boom spraying and droplets transporting process. The purpose of this study is to understand the gas and droplet two-phase flow fields and analyze the spraying distribution and droplets transporting under the different given operations of air assistance. The air-assisted spraying drift potential decreases with air-jet velocity. As the air-jet velocity is higher than 25m/s, the accretion of droplets on the upper surface of crop canopy focus on narrow areas. Air -assistance can reduce the drift of small droplets (50-200μm) effectively. In all cases, the angle between the air-jet and the nozzle is 0° or10°.