Numerical simulation of wake vortices of crop spraying aircraft close to the ground

A study of the velocity field of the wake of a Thrush 510G carrying out spray application close to the ground was investigated. The aircraft normally operates in extreme ground effect and wake vortices play a major role in the dispersal and deposition of pesticide spray released behind the aircraft. The evolution of wake vortices over time, and their interaction with the ground were simulated using computational fluid dynamics (CFD) techniques. The simulation was initialised with meteorological data from a field experiment. Information given by CFD simulation included the trajectory of the wake vortices as well as circulation, which indicates the strength of vortex. This information provided insights into the velocity field in the wake, including the upwash near the wing tips and the downwash in between. The effect of turbulence intensity as well as crosswind on the wake vortices and the resulting velocity field were investigated.