Thomas, P. J. (Peter J.) and Linden, P. F.. (2007) Rotating gravity currents: small-scale and large-scale laboratory experiments and a geostrophic model. Journal of Fluid Mechanics, Vol.57 . pp. 35-65. ISSN 0022-1120

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Abstract

Laboratory experiments simulating gravity-driven coastal surface currents produced by estuarine fresh-water discharges into the ocean are discussed. The currents are generated inside a rotating tank filled with salt water by the continuous release of buoyant fresh water from a small source at the fluid surface. The height, the width and the length of the currents are studied as a function of the background rotation rate, the volumetric discharge rate and the density difference at the source. Two complementary experimental data sets are discussed and compared with each other. One set of experiments was carried out in a tank of diameter 1 m on a small-scale rotating turntable. The second set of experiments was conducted at the large-scale Coriolis Facility (LEGI, Grenoble) which has a tank of diameter 13 m. A simple geostrophic model predicting the current height, width and propagation velocity is developed. The experiments and the model are compared with each other in terms of a set of non-dimensional parameters identified in the theoretical analysis of the problem. These parameters enable the corresponding data of the large-scale and the small-scale experiments to be collapsed onto a single line. Good agreement between the model and the experiments is found.

Item Type:	Journal Article
Subjects:	Q Science > QE Geology Q Science > QC Physics
Divisions:	Faculty of Science > Engineering
Library of Congress Subject Headings (LCSH):	Gravity -- Measurement, Water currents, Vortex-motion, Fluid dynamics
Journal or Publication Title:	Journal of Fluid Mechanics
Publisher:	Cambridge University Press
ISSN:	0022-1120
Date:	26 April 2007
Volume:	Vol.57
Page Range:	pp. 35-65
Identification Number:	10.1017/S0022112007004739
Status:	Peer Reviewed
Publication Status:	Published
Access rights to Published version:	Open Access
Funder:	Natural Environment Research Council (Great Britain) (NERC)
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URI:	http://wrap.warwick.ac.uk/id/eprint/678

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