General End-Depth–Discharge Relationship at Free Overfall in Trapezoidal Channel
Publication: Journal of Irrigation and Drainage Engineering
Volume 121, Issue 2
Abstract
There are relatively few investigations of the free overfall in a trapezoidal channel and its practical use as a flow-measuring device. The flow over a fall in a trapezoidal channel is simulated by that over a sharp-crested weir, taking into account the streamline inclination and curvature at the brink. A general end-depth–discharge relationship, for both subcritical and supercritical flow, is obtained. Discharges predicted using this general relationship are compared with experimental data and with those obtained from other theoretical methods. The surface profiles for the zone between the brink and an upstream section with hydrostatic pressure distribution are also investigated using the energy equation for both subcritical and supercritical flow.
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Information & Authors
Information
Published In
Journal of Irrigation and Drainage Engineering
Volume 121 • Issue 2 • March 1995
Pages: 143 - 151
Copyright
Copyright © 1995 American Society of Civil Engineers.
History
Published online: Mar 1, 1995
Published in print: Mar 1995
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