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On the energy deficiency in self-preserving convective flows

Published online by Cambridge University Press:  29 March 2006

J. S. Turner
Affiliation:
Department of Applied Mathematics and Theoretical Physics, University of Cambridge

Abstract

When similarity solutions are used to describe convective plumes or thermals, there is always found to be a discrepancy between the work done by buoyancy forces and the kinetic energy of mean motion. It is the main purpose of this paper to set down the ratio of these quantities for a wide variety of forms of buoyant elements and environmental stabilities. For consistency, the remaining fraction of the energy must appear as turbulent kinetic energy and eventually be dissipated, but these processes are not investigated in detail. The results are shown to have some relevance to the problem of convectively driven mixing across a density interface, where the largest scales of motion are dominant, and to the understanding of the transition zone between two self-preserving states of turbulent convection.

Type
Research Article
Copyright
© 1972 Cambridge University Press

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