Velocity Deformation Model for Unsteady Open-Channel Flows over Smooth and Rough Beds
Publication: Journal of Hydraulic Engineering
Volume 139, Issue 4
Abstract
A one-dimensional depth-averaged velocity deformation model is developed to study the characteristics of the unsteady flows in open channels. The vertical profile of the streamwise velocity is expressed in a power series, and the coefficients of the velocity are evaluated by using the unsteady equation of motion. A concise form of the friction velocity for unsteady nonuniform flow is then proposed by utilizing the coefficients of the power series. The applicability of the model is validated with experimental data, producing reasonably good agreement between the model results and the observed data. Finally, the deformation of velocity at the surface is assured by comparing velocity distribution of numerical model with the computational results from a previous model.
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Information & Authors
Information
Published In
Journal of Hydraulic Engineering
Volume 139 • Issue 4 • April 2013
Pages: 433 - 443
Copyright
© 2013 American Society of Civil Engineers.
History
Received: Apr 20, 2012
Accepted: Sep 18, 2012
Published online: Mar 15, 2013
Published in print: Apr 1, 2013
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