Convective Merging of Vortex Cores in LiftGenerated Wakes

The several wake vortices that originate from aircraft wingtips, flap edges, engine pylons, etc. usually merge, in the far field to form a single pair, whose structure determines the hazard posed to encountering aircraft. In order to gain an understanding of the process whereby vortices merge and disperse, a numercial study was made of the interaciton of two-dimension al, time-dependent, inviscid vortical regions. It was found that discrete boundaries, which depend on the structure and spacing of the vortices, distinguish merging from nonmerging situations. Furthermore, certain arrays of finite vortex cores that alternate in sign were found to undergo division and merging that may be useful in alleviating the hazard posed by aircraft wakes. AR b CL Ce Ct c c de d/