3 research outputs found
The Influence of Horizontal Boundaries on Ekman Circulation and Angular Momentum Transport in a Cylindrical Annulus
We present numerical simulations of circular Couette flow in axisymmetric and
fully three-dimensional geometry of a cylindrical annulus inspired by Princeton
MRI liquid gallium experiment. The incompressible Navier-Stokes equations are
solved with the spectral element code Nek5000 incorporating realistic
horizontal boundary conditions of differentially rotating rings. We investigate
the effect of changing rotation rates (Reynolds number) and of the horizontal
boundary conditions on flow structure, Ekman circulation and associated
transport of angular momentum through the onset of unsteadiness and
three-dimensionality. A mechanism for the explanation of the dependence of the
Ekman flows and circulation on horizontal boundary conditions is proposed.Comment: 23 pages, 7 figures; to be published in the Topical Issue of the
Physica Scripta in 200