A hybrid Lagrangian-dispersion model for spray drift prediction applied to horizontal boom sprayers

Abstract

A spray drift model for horizontal boom sprayers was developed, based on an earlier single nozzle model described by Renaudo et al. (2022). The extended model, which also includes droplets dispersion in the vertical direction, was successfully calibrated and then validated with field data from sources that covers different process conditions. In fact, the calculated spray drift values showed good agreement with reported measurements in a wide range of distances in the downwind direction. For the studied cases, the eddy diffusivity was found to be a function of the relative humidity. In the absence of dispersion-related data, the fitted equation can be used to fully predict spray drift from horizontal boom sprayers. The results indicated that, as the downwind distance increases, more nozzles contribute to the deposited flowrate and therefore accounting for them is necessary for a good representation of the spray drift. The model demonstrated to have low computational costs (time and resources) being then suitable to be used on board sprayer computers and web servers.