V-r vortex

From Glossary of Meteorology

V–R vortex

A two-dimensional circular flow in which an infinite vorticity is concentrated at the origin, the rest of the fluid being free of vorticity.

The (tangential) speed V is inversely proportional to the distance R from the origin:
If the flow is considered identical in all parallel planes, the vertical axis through the origin is a vortex filament.
See Rankine vortex.