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Vertical drift and reaction effects upon contaminant dispersion in parallel shear flows

Published online by Cambridge University Press:  21 April 2006

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

It is shown how the effects of the initial discharge profile, vertical drift, and boundary absorption (catalytic reaction) can be incorporated into a Gaussian approximation for the two-dimensional contaminant distribution in a parallel shear flow. Exact and asymptotic expressions are derived for the centroid displacement, shear-dispersion coefficient, and variance. Detailed results are presented for the effect of absorption at the bed and of vertical drift velocities upon contaminant dispersion in turbulent open-channel flow. For both cases the advantages of discharges close to the bed over surface discharges are made quantitative.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 165 , April 1986 , pp. 425 - 444
Copyright
© 1986 Cambridge University Press

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