Unsteady, Turbulent Convection into a Homogeneous, Rotating Fluid,with Oceanographic Applications

Abstract

Abstract Turbulent convection into a homogeneous, rotating fluid has been generated in laboratory tanks, for both laterally confined and unconfined domains. When a given experiment was in a solid-body rotation, a source located at the top surface of the water column was activated to release denser saltwater into the underlying, less-dense fluid of total depth H. As a result, a downward propagating 3D turbulent front was formed. Eventually, at a transition depth zc, rotational effects dominated the turbulence and many quasi-2D vortices were generated, which then penetrated downward beneath the upper 3D turbulent layer. Measurements in the confined experiments gave zc ≈ (12.7 ± 1.5) (B0/f3)1/2; the mean diameter (Dv) of the quasi-2D vortices as Dv≈(15.0±1.5) (B0/f3)1/2, their downward speed of propagation (uc) as uc ≈ (1.0 ± 0.1) (B0/f)1/2, and the maximum swirl velocity (uv) of an individual vortex as uv ≈ (4.0 ± 0.4)(B0/f)1/2 (where B0 is the surface buoyancy flux and f the Coriolis parameter). All are in...