Rotating turbulence

Abstract

Turbulence is characterised by non-linear transfer of energy and other invariants across an extended range of scales, from the injection scale to where dissipation is active. Many flow configurations in nature and in the laboratories deviate from the ideal homogeneous and isotropic turbulent cases (HIT) characterised by the presence of direct energy cascade only and strong small-scales universality. In the presence of other control parameters, as rotation, stratification, complex boundaries, etc. turbulence can assume different large-scale behaviour and different asymptotic regimes depending on the relative importance of the different mechanisms and on the intensity/quality of the symmetry-breaking at play. Nevertheless, for high Reynolds number, and for scales small enough, turbulence is believed to recover a sort of HIT universal behaviour. The boundaries in the control parameters phase-space (and across scales) between universal HIT behaviour and other rich physical regimes, including the existence of inverse cascade, formation of large-scale condensates, hysteresis, and different transport regimes of mass, heat and momentum is poorly understood. In many applications, it is not known if there exists real (phase)-transitions, asymptotic or pre-asymptotic regimes, non-commutative properties in the limiting protocols when sending the control parameters to their critical values and – more importantly – we have a very loose phenomenological control on the expected bulk flow properties. In this short review, we discuss some of the above-cited issues connected to Rotating Turbulence and we provide a short introduction to the scientific problems discussed by the invited contributions.