Laboratory Measurements of Void Fraction and Turbulence in the Bore Region of Surf Zone Waves
Publication: Journal of Engineering Mechanics
Volume 129, Issue 10
Abstract
Laboratory measurements of the instantaneous free surface, horizontal velocity, and void fraction fluctuations were made simultaneously for three cases of regular waves breaking on a plane slope. The data were reduced by ensemble averaging to quantify the temporal variation of the turbulence intensity and void fraction above trough level in the aeration region of the breaking waves. The cross-shore location of the measurements was restricted to the transition region marked by a rapid decrease in wave height. The study showed that the maximum ensemble-averaged void fractions were between 15 and 20% and that the temporal variation of the normalized void fraction above the still water level could be modeled by linear growth followed by exponential decay. The temporal variation of void fraction above the still water normalized by the wave period and average void fraction appears to be self-similar.
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Information & Authors
Information
Published In
Journal of Engineering Mechanics
Volume 129 • Issue 10 • October 2003
Pages: 1197 - 1205
Copyright
Copyright © 2003 American Society of Civil Engineers.
History
Received: Dec 14, 2001
Accepted: Jan 30, 2003
Published online: Sep 15, 2003
Published in print: Oct 2003
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