INTERACTION OF TURBULENCE AND LARGE-SCALE VORTICES IN INCOMPRESSIBLE 2D FLUIDS

It is commonplace in 2D fluid dynamics that intense large-scale vortic es arise during turbulence decay. Both the large-scale vortex and the turbulent components will be important in the further evolution: the v ortices will modify the turbulent dynamics and, in turn, will be modif ied by the turbulence. Using Wigner functions, we derive a new two-com ponent model to describe interaction of turbulence and intense large-s cale vortices in incompressible inviscid 2D fluids. We apply this mode l to study the dynamics of a vortex dipole propagating through turbule nce, a problem that allows an elegant analytic solution.