Effect of Rotation on a Developed Turbulent Stratified Convection: the Hydrodynamic Helicity, the Alpha-Effect and the Effective Drift Velocity

Abstract

An effect of rotation on a developed turbulent stratified convection is studied. Dependencies of the hydrodynamic helicity, the alpha-tensor and the effective drift velocity of the mean magnetic field on the rate of rotation and an anisotropy of turbulent convection are found. It is shown that in an anisotropic turbulent convection the alpha-effect can change its sign depending on the rate of rotation. Different properties of the effective drift velocity of the mean magnetic field in a rotating turbulent convection are found, e.g., there is a difference in the effective drift velocities for the toroidal and poloidal magnetic fields; a toroidal effective drift velocity can play a role of an additional differential rotation. These effects and an effect of a nonzero divergence of the effective drift velocity of the toroidal magnetic field on a magnetic dynamo are studied. Astrophysical applications of the obtained results are discussed.