Brink Depth in Nonaerated Overfalls
Publication: Journal of Irrigation and Drainage Engineering
Volume 111, Issue 4
Abstract
Small drop structures employed in irrigation canals are often not ventilated. In this paper the importance of the residual pressure at the brink of a rectangular overfall is quantified by means of the 1‐D momentum equation. The pressure acting below the nappe under nonaerated conditions is studied experimentally and correlated to the drop height in nondimensional terms. Comparison is made with relevant results for ventilated drop structures and criterion for defining a low drop is proposed. The results of pressure estimates are then used for a theoretical evaluation of the brink depth ratio as a function of the nondimensional drop height. The theoretical predictions are found to be in good agreement with the experimental results.
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References
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Information & Authors
Information
Published In
Journal of Irrigation and Drainage Engineering
Volume 111 • Issue 4 • December 1985
Pages: 395 - 403
Copyright
Copyright © 1985 ASCE.
History
Published online: Dec 1, 1985
Published in print: Dec 1985
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