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Buoyancy effects upon lateral dispersion in open-channel flow

Published online by Cambridge University Press:  19 April 2006

Ronald Smith
Affiliation:
Department of Applied Mathematics and Theoretical Physics, University of Cambridge

Abstract

A model equation is derived for the combined longitudinal and lateral dispersion of a buoyant contaminant in open-channel flow. The central hypotheses are that the water is shallow and that to a first approximation the effluent is vertically well mixed. The model includes allowance for the reduction in turbulent intensity due to weak vertical stratification, a buoyancy-driven secondary flow, and the redistribution of longitudinal momentum by the secondary flow. For a plume the theoretical results for the excess spreading due to buoyancy agree well with Prych's (1970) experimental results.

Type
Research Article
Copyright
© 1979 Cambridge University Press

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