Rotating Convection and Gravito-Inertial Wave Generation in Stellar Interiors

Abstract

Gravito-inertial waves can be excited at the interface of convective and radiative regions and by the Reynolds stresses in the bulk of the convection zone. The magnitude of their energy flux will therefore vary with the properties of the convection. To assess how convection changes with rotation, a simplified local monomodal model for rotating convection is presented that provides the magnitude of the rms velocity, degree of superadiabaticity, and characteristic length scale as a function of the convective Rossby number as well as with thermal and viscous diffusivities. In the context of this convection model, two models for assessing the gravito-inertial wave flux are considered: an interfacial model and a full treatment of the Reynolds stress impact on the waves. It is found that there are regimes where the sub-inertial waves may carry a significant energy flux relative to pure gravity waves that depend upon the convective Rossby number, the ratio of the buoyancy time-scale in the stable region to the convective overturning time, and the wave frequency.