Evaluation of spray pattern uniformity using three unique analyses as impacted by nozzle, pressure, and pulse-width...

Area of Science:

• Agricultural Engineering
• Precision Agriculture

Background:

• Pulse-width modulation (PWM) sprayers are increasingly popular, necessitating a thorough understanding of application interaction effects on spray pattern uniformity.
• Maintaining uniform spray overlap is crucial for reducing crop injury and maximizing pest coverage.

Purpose of the Study:

• To determine the impacts of nozzle type (venturi vs. non-venturi), boom pressure, and PWM duty cycle on spray pattern uniformity.
• To identify optimal settings for precise spray applications.

Main Methods:

• Utilized an indoor spray patternator at the University of Nebraska-Lincoln.
• Characterized spray pattern uniformity using Coefficient of Variation (CV), Root Mean Square Error (RMSE), and Average Percent Error (APE).

Main Results:

• PWM duty cycle had minimal impact on CV across nozzles and pressures.
• Increasing pressure decreased CV, improving uniformity, while RMSE generally increased with pressure and duty cycle.
• Average Percent Error (APE) increased significantly at lower duty cycles (20%), with non-venturi nozzles showing reduced APE at higher pressures.

Conclusions:

• PWM duty cycles at or above 40% minimally affect spray pattern uniformity.
• Higher application pressures and non-venturi nozzles improve the precision and uniformity of spray applications with PWM sprayers.