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A laboratory simulation of mixing across tidal fronts

Published online by Cambridge University Press:  26 April 2006

P. J. Thomas  and
P. F. Linden
P. J. Thomas
Affiliation:
Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Silver Street, Cambridge CB3 9EW, UK Present address: Department of Engineering, University of Wanvick, Coventry CV4 7AL, UK; e-mail: [email protected].
P. F. Linden
Affiliation:
Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Silver Street, Cambridge CB3 9EW, UK
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Abstract

A laboratory study which simulates the dynamics of shallow sea fronts and the mixing across a tidal front is described. The experiments show, for the first time, that it is possible to simulate a stationary tidal front with the inclusion of buoyancy effects, Coriolis effects and turbulence in the laboratory. Experimental data obtained for the cross-front mixing rate are presented. The data analysis shows that the mixing rate increases with stratification and decreases with rotation. A theoretical model of the flow which collapses the experimental data is developed which shows that the cross-front mixing is controlled by baroclinic processes. The model enables an extrapolation of the laboratory results to oceanographic conditions. Estimates of the cross-front mixing velocity for oceanographic conditions give values consistent with estimates obtained from North Sea data.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 309 , 25 February 1996 , pp. 321 - 344
Copyright
© 1996 Cambridge University Press

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