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The hydraulics of steady two-layer flow over a fixed obstacle

Published online by Cambridge University Press:  26 April 2006

Gregory A. Lawrence
Gregory A. Lawrence
Affiliation:
Department of Civil Engineering, University of British Columbia, Vancouver, BC, Canada, V6T 1Z4
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Abstract

This paper reports the results of a theoretical and experimental study of steady two-layer flow over a fixed two-dimensional obstacle. A classification scheme to predict the regime of flow given the maximum height of the obstacle, the total depth of flow, and the density and flow rate of each layer, is presented with experimental confirmation. There are differences between this classification scheme and that derived for flow over a towed obstacle by Baines (1984, 1987). These differences are due to the motion of upstream disturbances in towed obstacle flows. Approach-controlled flows, i.e. flows with an internal hydraulic control in the flow just upstream of the obstacle are studied in detail for the first time. This study reveals that non-hydrostatic forces, rather than a shock solution (called an internal hydraulic drop by previous investigators), need to be considered to explain the behaviour of Approach-controlled flows.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 254 , September 1993 , pp. 605 - 633
Copyright
© 1993 Cambridge University Press

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