Measurement and classification methods using the ASAE S572.1 reference nozzles
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United States Department of Agriculture Agricultural Research Service, 2771 F&B Road, College Station, Texas 77845, USA
Wilbur-Ellis, 4396 East Evans Road, San Antonio, Texas 75289, USA
University of Nebraska, 402 West State Farm Road, North Platte, Nebraska 69101, USA
Submission date: 2012-07-31
Acceptance date: 2012-09-17
Journal of Plant Protection Research 2012;52(4):447–457
An increasing number of spray nozzle and agrochemical manufacturers are incorporating droplet size measurements into both research and development. Each laboratory invariably has their own sampling setup and procedures. This is particularly true about measurement distance from the nozzle and concurrent airflow velocities. Both have been shown to significantly impact results from laser diffraction instruments. These differences can be overcome through the use of standardized reference nozzles and relative spray classification categories. Sets of references nozzles, which defined a set of classification category thresholds, were evaluated for droplet size under three concurrent air flow velocities (0.7, 3.1 and 6.7 m/s). There were significant, though numerically small, differences in the droplet size data between identical reference nozzles. The resulting droplet size data were used to categorize a number of additional spray nozzles at multiple pressure and air flow velocities. This was done to determine if similar classifications were given across the different airspeeds. Generally, droplet size classifications agreed for all airspeeds, with the few that did not, only differing by one category. When reporting droplet size data, it is critical that data generated from a set of reference nozzles also be presented as a means of providing a relative frame of reference.
The authors have declared that no conflict of interests exist.
Zbigniew Czaczyk
United States Department of Agriculture Agricultural Research Service, 2771 F&B Road, College Station, Texas 77845, USA
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