Equivalent Roughness of Submerged Obstacles in Open-Channel Flows
Publication: Journal of Hydraulic Engineering
Volume 140, Issue 2
Abstract
Experimental results for flow in a 16.5% sloping channel over various kinds of submerged artificial large-scale roughness elements are presented. Eight different shapes of obstacles are tested, as follows: (1) standard baffle blocks, (2) cubes, (3) half-cubes, (4) angles, (5) cylinders, (6) vertical rods, (7) hemispheres parallel to the flow, and (8) hemispheres normal to the flow. Based on depth measurements, the effective Manning’s coefficient is determined and the respective equivalent sand roughness is evaluated. The results are given in nondimensional terms and compared with previous research. The effects of shape, size, and density of the obstacles on flow resistance are discussed.
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Acknowledgments
Original data have been obtained by Eleni Kostidou and Petros Vassilakos in the course of their diploma theses at the National Technical University of Athens.
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Information & Authors
Information
Published In
Journal of Hydraulic Engineering
Volume 140 • Issue 2 • February 2014
Pages: 226 - 230
Copyright
© 2014 American Society of Civil Engineers.
History
Received: Nov 8, 2012
Accepted: Jul 1, 2013
Published online: Jul 4, 2013
Discussion open until: Dec 4, 2013
Published in print: Feb 1, 2014
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