Free-Surface Profiles, Velocity and Pressure Distributions on a Broad-Crested Weir: A Physical Study
Publication: Journal of Irrigation and Drainage Engineering
Volume 138, Issue 12
Abstract
Basic experiments were conducted on a large-size broad-crested weir with a rounded corner. Detailed free-surface, velocity, and pressure measurements were performed for a range of flow conditions. The results showed the rapid flow distribution at the upstream end of the weir and next to the weir brink at large flow rates. The flow properties above the crest were analyzed taking into account the nonuniform velocity and nonhydrostatic pressure distributions. Introducing some velocity and pressure correction coefficients, it is shown that critical flow conditions were achieved above the weir crest for . The velocity measurements highlighted a developing boundary layer. The data differed from the smooth turbulent boundary layer theory, although the present results were consistent with earlier studies. On average, the boundary stress was approximately 0.0015–0.0025.
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Acknowledgments
The authors thank Ahmed Ibrahim and Jason Van Der Gevel (The Univ. of Queensland) for the technical assistance. The financial support of the Australian Research Council (Grant DP0878922) is acknowledged. The first author was supported by a Univ. of Queensland research scholarship.
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Published In
Journal of Irrigation and Drainage Engineering
Volume 138 • Issue 12 • December 2012
Pages: 1068 - 1074
Copyright
© 2012 American Society of Civil Engineers.
History
Received: Aug 11, 2011
Accepted: Jun 1, 2012
Published online: Jul 27, 2012
Published in print: Dec 1, 2012
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