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ARS Home » Plains Area » College Station, Texas » Southern Plains Agricultural Research Center » Aerial Application Technology Research » Research » Publications at this Location » Publication #398992
Research Project: Improved Aerial Application Technologies for Precise and Effective Delivery of Crop Production Products

Location: Aerial Application Technology Research

Title: The physics of spray droplets released from ag aircraft

Author
item Fritz, Bradley - Brad

Submitted to: Agricultural Aviation
Publication Type: Popular Publication
Publication Acceptance Date: 9/26/2022
Publication Date: 10/26/2022
Citation: Fritz, B.K. 2022. The physics of spray droplets released from ag aircraft. Agricultural Aviation. 49(4):44-49.

Interpretive Summary: Spray drift is an ongoing critical concern that all aerial applicators are responsible for understanding and accounting for when setting up their aircraft to make an application. We adapted spray drift modeling algorithms to illustrate how spray droplets of different sizes are carried within the aircraft's air flow fields and how changing the location of the nozzle can significantly impact where the droplets are carried and deposited. Results showed that smaller droplets that are released closer to the wing tips remain in the air significantly longer and are carried farther downwind than larger droplets positioned closer to the aircraft body. Further, higher wind speeds and release heights result in greater suspension times and deposition farther downwind of the application site. The results emphasize the need for spray systems to be properly set up to account for the aircraft flow fields in order to minimize spray drift and off-target damage.

Technical Abstract: Spray drift is an ongoing critical concern that all aerial applicators are responsible for understanding and accounting for when setting up their aircraft to make an application. Scientists with the USDA-ARS Aerial Application Technology Research Unit adapted spray drift modeling algorithms to illustrate how spray droplets of different sizes are carried within the aircraft's air flow fields how changing the location of the nozzle can significantly impact where the droplets are carried and deposited. Results that smaller droplets that are release closer to the wing tips remain in the air significantly longer and are carried further downwind that larger droplets position closer to the aircraft body. Further, higher wind speeds and release heights result in greater suspension times and deposition further downwind of the application site. The results emphasize the needs for spray systems to be properly setup to account for the aircraft flow fields in order to minimize spray drift and off-target damage.