Channel Shape and Turbulence Issues in Flood Flow Hydraulics
Publication: Journal of Hydraulic Engineering
Volume 131, Issue 10
Abstract
This paper reports the results of some further reflections by the writer on the nature of the flow physics in flooded channels where the floodplain flow overtops that in the main channel. A lot of the early conclusions drawn on this issue come from results of the Flood Channel Facility (FCF) program carried in the United Kingdom in the 1990s, but also from numerical work such as that of the writer. This paper takes this work further and reports that the FCF geometry may have led to conclusions that are dependent on a channel layout that is not fully representative of nature. It indicates that the flow structure evolves as a function of the channel width-to-depth ratio, and requires different turbulence model approaches to be computed accurately as this happens. In particular the standard is shown to become less adequate. It is also shown that the bank slope is influential in determining the flow structure, and that the flatter the slope the more likely it is to present increasing difficulties for modeling.
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Acknowledgments
The writer would like to thank Dr. Florian Menter from CFX Germany for his comments and pictures as well as Professor Alan Ervine, The University of Glasgow, for his information regarding the FCF geometry.
References
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Information & Authors
Information
Published In
Journal of Hydraulic Engineering
Volume 131 • Issue 10 • October 2005
Pages: 862 - 865
Copyright
© 2005 ASCE.
History
Received: Oct 21, 2003
Accepted: Dec 1, 2004
Published online: Oct 1, 2005
Published in print: Oct 2005
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