Water Surface Characteristics of Submerged Rectangular Sharp-Crested Weirs
Publication: Journal of Hydraulic Engineering
Volume 142, Issue 5
Abstract
Laboratory experiments were carried out to investigate the water surface characteristics of submerged flow over sharp-crested weirs. Interesting observations were made on the water surface profiles near the weir as weir submergence sets in as well as for various stages of submergence. Submerged flow was divided into four regimes: (I) impinging jet, (II) surface jump, (III) surface wave, and (IV) surface jet. It was found that a surface jump turned into a surface wave when the wave trough became level with the tip of the weir. The surface jet regime began as the surface waves faded out. A condition was set to quantify the boundary between the surface wave and surface jet regimes. Based on flow observations, the surface jet regime sets in as the amplitude of the surface wave becomes small (i.e., less than , where is the head). An empirical equation was developed based on the literature data to predict the discharge reduction factor in the generally used discharge equation. This formulation was compared with other formulations in the literature. It was found that the proposed formulation provides a slightly better estimation of flow discharge.
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Published In
Journal of Hydraulic Engineering
Volume 142 • Issue 5 • May 2016
Copyright
© 2016 American Society of Civil Engineers.
History
Received: Jan 16, 2015
Accepted: Sep 23, 2015
Published online: Jan 6, 2016
Published in print: May 1, 2016
Discussion open until: Jun 6, 2016
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