Student Posters Repository

Homogeneous background rotation, through the Coriolis force, affects the energy transfer and isotropy within the turbulent kinetic energy cascade. For strong rotation, i.e., sufficiently small Rossby numbers, backward transfer from small to large scales becomes significantly important and leads to the formation of columnar eddies elongated along the axis of rotation. In numerical investigations of rotating turbulence, the growth of such columnar eddies is artificially constrained by the finite domain size and periodic boundary conditions. As a remedy, larger computational domains must be considered. Through Direct Numerical Simulation (DNS) of different relative domain sizes, we show that the strength of the inverse energy cascade and, therefore, the amount of energy that is accumulated at the large scales, depends on the ratio of integral length-scales to domain size. Furthermore, our data suggests that, for sufficiently large domains, the integral length-scale parallel to the axis of rotation grows linearly in time. It's growth rate, however, is strongly influenced by the domain size.