Modeling finer droplet aerial spray drift and deposition

Aerial application models represent the effects present in the near wake of the aircraft by simple models approximating the detailed physics found the re. The important inputs into these models include the aircraft characteris tics, flight parameters, meteolological conditions, tank mix characteristic s, and droplet size distribution. Many numerical studies have shown that re lease height, wind speed and nozzle atomization nl-e the main contributing factors to spray drift. With control of release height and wind speed essen tially an application issue at the time of spraying, control of the droplet size distribution call be done well ahead of time and with deliberate inte nt. In this regard spray quality classification appears to be overtaking th e industry today especially in light of the development of ASAE S-572, In t his article We explore the deposition and drift of the smallest droplets (f ine fraction) at the limit of the classification scheme, ir? particular rea ching towards, a very-fine droplet sizes, typical of ultra low volume (ULV) spraying.