Critical Flow over Circular Crested Weirs
Publication: Journal of Hydraulic Engineering
Volume 134, Issue 11
Abstract
The critical flow principle is a useful approach for the hydraulic analysis of round-crested weirs due to their single head-discharge relationships. The hydraulics of circular-crested weirs is examined using simplified models incorporating streamline curvature effects, comparing their predictions with experimental data. A generalized one-dimensional model based on the critical flow in curvilinear motion has been developed. The discharge coefficient increases with the specific energy normalized with the radius of curvature, , when streamline curvature effects are included. The relative flow depth at the crest decreases as increases. The flow at the weir crest is only critical for a normalized specific energy value of . For larger heads, the flow at the weir crest has been found to be supercritical.
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Acknowledgments
The senior writer wants to express his deep gratitude to Professor Willi H. Hager, VAW at ETH Zurich, for the helpful information, without which the present work could not have been carried out. The motivating long-distance help of Professor Sergio Montes from the University of Hobart, Tasmania, as well as the assistance of Professor Hubert Chanson of the Department of Civil Engineering of the University of Queensland, Brisbane, Australia are also greatly appreciated.
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© 2008 ASCE.
History
Received: Oct 20, 2006
Accepted: Feb 29, 2008
Published online: Nov 1, 2008
Published in print: Nov 2008
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