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Diffusion in shear flows made easy: the Taylor limit

Published online by Cambridge University Press:  21 April 2006

Ronald Smith
Affiliation:
Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Silver Street, Cambridge CB3 9EW, UK

Abstract

G. I. Taylor (1953) gave a simple recipe for the calculation of contaminant dispersion in bounded shear flows at large times after discharge. He decomposed the concentration profile across the flow into a resolved (uniform) part, with an equilibrium (large-time) estimate for the unresolved part. Here an extended recipe is given to include greater resolution and earlier validity. At the two-equation level there is a close similarity to the slow-zone model posed by Chikwendu & Ojiakor (1985). Application is given to Poiseuille pipe flow and to a contraflowing parallel-plate heat exchanger.

Type
Research Article
Copyright
© 1987 Cambridge University Press

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