Motion of a two-dimensional monopolar vortex in bounded rectangular domain

In this paper we describe results of a study of the two-dimensional motion of a distributed monopolar vortex in a viscous incompressible fluid in a bounded rectangular domain with free-slip and no-slip boundary conditions. In the case of free-slip walls the motion of the vortex center can be satisfactorily modelled by a single point vortex in an inviscid fluid. Comparison of the results of both models reveals a good quantitative agreement for the trajectories of the vortex centers and of the period of one revolution around the center of the domain, for moderate viscous effects (Re=1000 and more). In a domain with no-slip walls the distributed monopolar vortex moves to the center of the domain along a curved but not smooth trajectory due to the interaction of the monopole and the wall-induced vorticity.