Single nozzle spray drift measurements of drift reducing nozzles at two forward speeds

Stallinga, H.; Zande, J.C. van de; Michielsen, J.G.P.; Velde, P. van


In 2011‒2012 single nozzle field experiments were carried out to determine the effect of different flat fan spray nozzles of the spray drift reduction classes 50, 75, 90 and 95% on spray drift at two different forward speeds (7.2 km h-1 and 14.4 km h-1). Experiments were performed with a single nozzle spraying on an outdoor spray track perpendicular to the wind direction. Nozzle types were compared with the BCPC threshold nozzle Fine/ Medium and a standard flat fan nozzle TeeJet XR11004. Ground deposits were measured from 1 m upwind to 10 m downwind with respect to the nozzle. At 5 and 10 m distances, airborne spray drift was measured with passive and active collectors. Differences in spray
drift reduction were measured for the different nozzle types. Results showed that with a higher nozzle forward speed the spray drift deposition increased for both the ground deposition and the airborne spray drift. Higher nozzle forward speeds may lead to nozzles to be classified in a lower spray drift reduction class.