Hydraulic Relations for Clinging Flow of Sharp-Crested Weir
Publication: Journal of Hydraulic Engineering
Volume 136, Issue 6
Abstract
Available discharge coefficient formulas for sharp-crested weirs are only applicable to the free-flow regime. To extend the range of discharge measurement by a rectangular sharp-crested weir, critical heads of the transition flow regime, the head-discharge relation for clinging and free flow, and the discharge coefficient for clinging flow were investigated experimentally based on more than 300 experimental points with head ranging from 0.0048 to 0.0455 m. The results indicate that the transitions from clinging to free flow and vice versa do not occur at the same head. Upper and lower critical heads, and , can be identified at which these transitions occur. For the condition studied, the head relation between clinging and free flow is found to be linearly correlated at the same discharge. Expressions for the discharge coefficient for clinging flow are developed.
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Acknowledgments
This work was partially supported by the National Key Technologies R and D Program for the 11th Five-Year Plan (Grant No. UNSPECIFIED2006BAJ04B03-2), the Program for Changjiang Scholars and Innovative Research Team in University, and the Program for Beijing Key Subject of Hydrology and Water resources.
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Information & Authors
Information
Published In
Journal of Hydraulic Engineering
Volume 136 • Issue 6 • June 2010
Pages: 385 - 390
Copyright
© 2010 ASCE.
History
Received: Jan 6, 2008
Accepted: Nov 13, 2009
Published online: May 14, 2010
Published in print: Jun 2010
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