Evaluation of Liquid Atomization and Spray Drift Reduction of Hydraulic Nozzles with Four Spray Adjuvant Solutions

Abstract

The droplet size distribution following pesticide application practices can significantly impact droplet drift and non-target organisms (animals and plants). However, the relationship among liquid sheet breakup, drop formation, and droplet drift is an area that has been studied over the past 65 years but is still not fully understood. The objectives of this study were severalfold: to examine the liquid sheet breakup following the use of different adjuvants (sodium dodecyl sulfate, aerosol OT, and silicone at 1%) and their effects on the drift via three commonly used commercial spray nozzles (XR, AIXR, and TXVK). The spray sheet and initial droplet size spectrum for each spray was detected by a particle image velocimetry (PIV) system, and the drift for each treatment was measured in a wind tunnel. The nozzle type and the spray solution were found to significantly affect the liquid sheet breakup characteristics. AIXR produced large droplets, and TXVK with short liquid sheet length produced more small droplets. All adjuvants used in these experiments increased the formation of large droplets upon atomization while simultaneously reducing driftable fines (e.g., drops %<150 µm). The drift potential can be reduced by up to 66.1% when switching from a fine spray quality (TXVK) to a coarse spray quality (AIXR). The SDS adjuvant provided the most effective drift reduction for XR and TXVK nozzles showing reduced drift potential by 69.2% and 66.3%, respectively, while the silicone adjuvant showed the largest drift reduction for AIXR of 78.3%. The correlation between the liquid sheet length and DV0.5 was positive for XR and TXVK nozzles, and there was a significant positive correlation between %<150 µm and drift potential for all nozzles. This work suggests that the drift can be reduced significantly by changing the nozzle type and adding pesticide adjuvant into spray solution, which provided data support for the drift reduction of plant protection drones.

Application of Unmanned Aerial Vehicles in Precision Agriculture

“…The experimental results also show that the spray additives strongly affect reductions in the drift of the fog droplets. Liu et al evaluated the spray drift reduction effect of four different spray auxiliaries during the liquid atomization of hydraulic nozzles [7]. Three commonly used commercial nozzles (XR, AIXR, and TXVK) were examined in terms of spray effects with different adjuvants (sodium dodecyl sulfate, aerosol OT, and 1% silicone).…”

Anti-Drift Technology Progress of Plant Protection Applied to Orchards: A Review

“…Moreover, variable spraying technology is an actively researched topic. Sensors can be used to detect fruit tree canopy characteristics and meteorological parameters according to the canopy information to achieve real-time control of the spray system and the airflow delivery system, as well as real-time adjustment of the application program precision application, which can effectively reduce the amount of drift [26].…”