ID 315

An Empirical Model for Spray Drift Potential Estimation based on Hydraulic Nozzle Spray Characteristics

 

Abstract:

Spray drift is the movement of pesticide droplets through the air, during and after application, to unintended sites; drift can damage sensitive neighboring crops, hurt wildlife, and contaminate water supplies.

This study hypothesized that it is possible to predict spray drift potential based on the knowledge of nozzle spray characteristics.

The aim of the study was to quantify this relationship by: •collecting experimental data for nozzle spray characteristics (i.e., droplet size and -velocity distribution in the spray, spray fan width and flow rate through the nozzle at a given liquid pressure) for a broad variety of nozzles •measuring the potential spray drift in a wind tunnel •developing an empirical model based on experimental data for 10 hydraulic spray nozzles

Droplet size and velocity were analyzed using laser-based equipment (Phase Doppler Anemometry), spray liquid distribution from a single nozzle was analyzed using a mechanical spray pattern analyzer, and spray drift potential was analyzed in a wind tunnel at wind speeds of 2, 4, and 6 m/s.

The empirical model was developed based on the experimental data. The model predicted the spray drift potential of the studied nozzle types, and can be assumed to predict that of other nozzles or liquid pressures if the spray characteristics are known.