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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 #318115

Title: A practical interpretation and use of the USDA aerial fixed-wing nozzle models

item Fritz, Bradley - Brad
item Hoffmann, Wesley
item BRETTHAUER, SCOTT - University Of Illinois

Submitted to: Applied Engineering in Agriculture
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/21/2015
Publication Date: 1/29/2016
Citation: Fritz, B.K., Hoffmann, W.C., Bretthauer, S. 2016. A practical interpretation and use of the USDA aerial fixed-wing nozzle models. Applied Engineering in Agriculture. 32(1):29-35.

Interpretive Summary: Successful aerial applications start with proper spray nozzle selection, setup and operation to ensure the resulting droplet size meets both label requirements and meteorological and geographical conditions at the site of application. Recent computational droplet size models developed by unit scientists provide applicators a tool that can be used when making selections and operational decisions, however, in their current format the models may require iterative calculations that can frustrate users and ultimately lead to non-usage. Using the computational models, graphical representations of each nozzles full operational spectrum were developed with droplet size classification data visually represented across the whole space. The new graphical interfaces greatly enhance the usability of the aerial nozzle models allowing applicators to more quickly make operational decisions and document applications parameters in order to meet pesticide product labels and ultimately optimize applications.

Technical Abstract: Proper selection and operation of spray nozzles associated with aerial applications is critical to insuring efficacy while mitigating off-target movement. Labels for most agrochemical products applied in the U.S. specifically define the droplet size or spray classification that can be used to apply that product. Droplet size associated with most aerial application nozzles is a function of the combination of orifice size, spray pressure, orientation angle, and airspeed used. Recently a set of computational models for the most commonly used aerial application nozzles were developed and released for use by applicators. While these models allow applicators to determine the droplet size characteristics associated with their specific nozzle and operational setup, determining the proper combination of orifice, pressure, orientation and airspeed, can be an interactive process, leading to frustration and ultimately non-use of the models. To minimize the iterative calculations and provide a more intuitive, visual interpretation of the computational droplet size models, a series of graphical representations of each nozzles complete operational space were developed for use by applicators. These graphical interfaces allow for optimal operational combinations to be more quickly identified and integrated into the application system setup decision matrix. The ultimate goal of this work is to increase the usage rate of the computational spray droplet size models by aerial applicators by providing a more intuitive and efficient user interface.