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Measuring Surface Wind Velocity Changes
Agricultural and Biosystems Engineering Conference Proceedings and Presentations
  • Matthew W. Schramm, Iowa State University
  • H. Mark Hanna, Iowa State University
  • Matthew J. Darr, Iowa State University
  • Steven J. Hoff, Iowa State University
  • Brian L. Steward, Iowa State University
Document Type
Conference Proceeding
Publication Version
Published Version
Publication Date
Conference Title
2015 ASABE Annual International Meeting
Conference Date
July 26–29, 2015
(29.95106579999999, -90.0715323)
Agricultural spray drift is affected by many factors ranging from current weather conditions and the topography of the surrounding area, to the properties at the nozzle and the height at which the spray is released. Wind direction, speed, and solar radiation during the late spring/summer spray season of 2014 was measured at 10 Hz. Instrumentation was placed one meter off the ground to simulate conditions of a sprayer. Data was used to measure wind changes as it moved from one sensor to another, and to evaluate under what conditions wind may be most likely to have a significant direction or speed change. The data suggests that little to no linear correlation exists between an upwind and downwind sensors when measured in one minute segments, after adjusting for lag between the two sensors. The linear correlation values for wind direction and speed were 0.28 and 0.20 respectively. The downwind sensor measured a wind direction greater than 20 degrees different from the upwind sensors 16% of the time. The downwind sensor measured 1 m/s different wind speed from the upwind sensor 40% of the time. Histograms of wind big change events, where the difference in wind direction 30 seconds in the future and the current wind direction was greater than a set tolerance, were created for tolerances of 5, 25, and 45 degrees. For all tolerances, lower wind speeds (< 3 m/s) gave rise to more wind change events.

This proceeding is from 2015 ASABE Annual International Meeting, Paper No. 152182031, pages 1-15 (doi: 10.13031/aim.20152182031). St. Joseph, Mich.: ASABE. Posted with permission.

Copyright Owner
American Society of Agricultural and Biological Engineers
File Format
Citation Information
Matthew W. Schramm, H. Mark Hanna, Matthew J. Darr, Steven J. Hoff, et al.. "Measuring Surface Wind Velocity Changes" New Orleans, LA, United States(2015)
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