Near field dynamics of wing tip vortices

An experimental investigation has been conducted to study the formation and near-field dynamics of a wing tip vortex. Stereoscopic PIV (SPIV), which allows instantaneous measurements of all three components of velocity within a planar slice, was used to measure velocity fields behind the wing. The present study has found that the wing sheds multiple vortices of opposite signs. Farther downstream, the vortices, with opposite sense of rotation, break up into smaller vortices which satellite around the tip vortex. At least one relatively strong satellite vortex appears in some of the instantaneous fields. The study found that the interaction of the tip vortex and satellite vortices give rise to the unsteady motion of the wing tip vortex.