论文信息 - A simulation model of the spray drift from hydraulic nozzles

A simulation model of the spray drift from hydraulic nozzles

Abstract A model to predict the trajectories of droplets from agricultural flat fan nozzles is described. Droplet motion is considered in two phases: close to the nozzle where the trajectory is dominated by the conditions associated with droplet formation, particularly the initial velocity and entrained air conditions; and a second phase where the effects of atmospheric turbulence are predicted using a “random-walk” approach. Results from the model are compared with laboratory measurements of droplet size/velocity profiles beneath a nozzle and with field measurements of the downwind drift from boom mounted nozzles operated conventionally. Predicted total downwind drift deposits agreed well with measured values but the form of the vertical deposit distribution was less well predicted.

P.C.H. Miller | D. J. Hadfield | P. Miller | D. Hadfield

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