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An experimental study of the upwelling response of stratified reservoirs to surface shear stress

Published online by Cambridge University Press:  21 April 2006

Stephen Monismith
Affiliation:
Hydraulic Engineering Laboratory, Department of Civil Engineering, University of California, Berkeley, CA 94720, USA Present address: Centre for Water Research, University of Western Australia, Nedlands, WA 6009, Australia.

Abstract

An experimental study of the dynamic response of non-rotating, stratified reservoirs to the application of surface shear stresses is presented. The experiments were made using two-layered and linear stratifications; a moving belt was used to supply a shear stress to the fluid. Detailed measurements of the density field show that upwelling occurs at all values of the Wedderburn number, W, rather than only occurring when W < 1. Differences between the two-layer theory and the present observations are attributed to the fact that the experimental stratifications were continuous, rather than layered. Shearflow dispersion is observed to be an important mechanism for distributing the effects of localized upwelling over the entire length of the mixed layer. A model of mixed-layer deepening based on upwelling and shearflow dispersion is presented and is compared to the observations of this and other experimental studies.

Type
Research Article
Copyright
© 1986 Cambridge University Press

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