A Note on the Mixing of Angular Momentum in a Neutrally Buoyant Fluid

Abstract

The effect of turbulent mixing in a neutrally buoyant rotating fluid is considered in a region where the mean flow is axisymmetric. The separate actions of molecular and turbulent mixing are distinguished. It is shown that a rotating turbulent flow capable of mixing angular momentum must vary in the axial direction. In particular, it would seem that a secondary circulation is required for a flow to support turbulence over its whole volume. The relative roles of turbulence and secondary circulations in the mixing of angular momentum are discussed.