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On the slow motion of a spheroid in a rotating stratified fluid

Published online by Cambridge University Press:  04 November 2016

E. R. Johnson*
Affiliation:
Department of Mathematics, University College London, London WC1E 6BT, UK
Stefan G. Llewellyn Smith
Affiliation:
Department of Mechanical and Aerospace Engineering, Jacobs School of Engineering, UCSD, La Jolla, CA 92093-0411, USA
*
Email address for correspondence: e.johnson@ucl.ac.uk

Abstract

We consider the slow motion generated when a body is set into motion relative to an incompressible, inviscid, non-diffusive rotating stratified fluid, showing that there is generated in general a topographic Rossby wave which leads to non-decaying fluctuations in the lift on the obstacle and a fluctuating non-zero drag. The problem is relevant to the flow patterns and forces excited when slow oceanic flows cross bottom topography, and suggests a mechanism for slow fluctuations observed in laboratory experiments.

Type
Rapids
Copyright
© 2016 Cambridge University Press 

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