Theoretical and experimental studies on the oil-based emulsion spray.

Area of Science:

• Agricultural Engineering
• Fluid Dynamics
• Spray Technology

Background:

• Oil-based emulsions are common herbicide formulations with unique atomization properties compared to water sprays.
• Understanding spray droplet size is crucial for effective herbicide application and minimizing drift.

Purpose of the Study:

• To develop and validate a theoretical model for predicting spray droplet size in oil-based emulsion agricultural sprays.
• To analyze the atomization mechanism of oil-based emulsion sprays, focusing on their characteristic web structure.

Main Methods:

• Proposed a theoretical model incorporating nozzle exit size, spray sheet angle, and web structure perforation number.
• Employed image processing to measure droplet size distributions under varying spray pressures and nozzle configurations.
• Validated the theoretical model against experimental measurements of droplet size distribution.

Main Results:

• Oil-based emulsion sprays exhibit a distinct web structure with perforations where liquid collects.
• The theoretical model shows droplet size is inversely proportional to the square root of the perforation number and directly proportional to the square root of the nozzle exit area.
• Experimental results demonstrated consistency with theoretical predictions, with less than 10% difference in volumetric median diameter.

Conclusions:

• The developed theoretical model provides a reliable method for predicting spray droplet size in oil-based emulsion agricultural sprays.
• The model's reliance on easily obtainable parameters (nozzle size, spray angle, perforation number) makes it practical for agricultural applications.
• The findings enhance the understanding of oil-based emulsion spray atomization, crucial for optimizing herbicide delivery.