Vortex dynamics in rotating Rayleigh–Bénard convection

We investigate the spatial distribution and dynamics of the vortices in rotating Rayleigh.Benard convection in a reduced Rayleigh-number range 1.310Rac), the vortices are randomly distributed. The size-distribution of theVoronoi cells of the vortex centers is well described by the standard 1' distribution. In thisflow regime the vortices exhibit Brownian-type horizontal motion. The probability densityfunctions of the vortex displacements are, however, non-Gaussian at short time scales. Amodestrotating rates (4Ra < Ra<10Rac)the centrifugal force leads to radial vortex motions.i.e., warm cyclones (cold anticyclones) moving towards (outward from) the rotation axis. Themean-square-displacements of the vortices increase faster than linearly at large time. Thissuper-diffusive behavior can be satisfactorily explained by a Langevin model incorporatingthe centrifugal force. In the rapidly rotating regime (1.6Rac