On Decaying Two-Dimensional Turbulence in a Circular Container

Direct numerical simulation of two-dimensional decaying turbulence in a circular container with no-slip boundary conditions are presented. Starting with random initial conditions the flow rapidly exhibits self-organisation into coherent vortices. We study their formation and the role of the viscous boundary layer on the production and decay of integral quantities. The no-slip wall produces vortices which are injected into the bulk flow and tend to compensate the enstrophy dissipation.