Motion of two vortex rings (Q1082930)

It is well-known that two coaxial rings which are moving in the same direction pass through each other alternately. In the case of thin vortex rings this phenomenon was first considered. The assumption that the vortex rings are thin means that when their interaction is considered they can be assumed to be annular vortex filaments. Certain new properties are determined for a system of two coaxial vortex rings of the same intensity.