Authors: Batalov V.G., Sukhanovsky A.N., Frick P.G.
Year: 2009
Issue: 04
Pages: 13-19
Abstract
The evolution of a large-scale azimuthal velocity field in a rotating cylindrical layer of fluid (radius 150 mm, depth 30 mm, free upper surface) with meridional convective circulation was studied experimentally. Two cases were considered: inward upper level circulation provided by a rim heater at the periphery and outward upper level circulation provided by a central heater. The heating rate is characterized by the Grashoff number defined through the heat flux. The detailed 3D structure of the mean large-scale velocity field is reconstructed using the PIV technique for large interval of Grashoff number values. It was shown that the energy of meridional circulation grows with the Grashoff number in the same way for both directions of circulation. Due to the action of the Coriolis force the meridional flow results in differential rotation. Meridional circulation leads to substantial variation of the integral angular momentum. Inward circulation results in the growth of the integral angular momentum and outward circulation causes it to decrease. At the same heating power, the increase of angular momentum at inward circulation is much stronger than its decrease at outward circulation.
Tags: angular momentum; differential rotation; meridional circulation; super-rotation
Bibliography
- Gierasch, P.J (1975) Meridional Circulation and the Maintenace of the VenusAtmospheric Rotation. J. Atmos. Science, Vol. 32, pp. 1038.
- Read, P.L. (1986) Super-rotation and diffusion of axial angular momentum: I. “Speedlimits” for axisymmetric flow in a rotating cylindrical fluid annulus. J.R. Met. Soc., 112, pp.231–252.