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Experiments on the dynamics of a gravity current head

Published online by Cambridge University Press:  19 April 2006

R. E. Britter  and
J. E. Simpson
R. E. Britter
Affiliation:
Department of Applied Mathematics and Theoretical Physics, University of Cambridge
J. E. Simpson
Affiliation:
Department of Applied Mathematics and Theoretical Physics, University of Cambridge
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Abstract

Some of the dense fluid at the front of an advancing gravity current is observed to be mixed with the ambient fluid. This process continues when the cross-stream non-uniformities at the head of the current are suppressed by advancing the floor beneath the head. In the resulting two-dimensional flow regular billows are visible. This paper considers experimentally and analytically the inviscid gravity current head and specifically includes the observed mixing at the head. Experimental results were obtained with an apparatus in which the head of the gravity current was brought to rest by an opposing uniform flow. The mixing appears to occur through Kelvin-Helmholtz billows generated on the front of the head and controls the dynamics of the head. A momentum balance is used to analyse the flow and the problem is closed by quantitatively introducing the billow structure.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 88 , Issue 2 , 27 September 1978 , pp. 223 - 240
Copyright
© 1978 Cambridge University Press

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