Deformation and Splitting of Pseudo-elliptical Vortex Rings

Abstract

A vortex-dynamics simulation has been made on the deformation of a pseudo-elliptical vortex ring which consists of two parallel line segments connected by two semicircles of the same radius, the major-to-minor axis ratio being between 2 and 20. The deformation has four fundamental patterns depending on the aspect ratio: the periodic axis switching; the splitting into two vortex rings after the axis switching; the splitting into two vortex rings without the axis switching; the splitting into three vortex rings without the axis switching.