Depth-Averaged Shear Stress and Velocity in Open-Channel Flows
Publication: Journal of Hydraulic Engineering
Volume 136, Issue 11
Abstract
Turbulent momentum and velocity always have the greatest gradient along wall-normal direction in straight channel flows; this has led to the hypothesis that surplus energy within any control volume in a three-dimensional flow will be transferred toward its nearest boundary to dissipate. Starting from this, the boundary shear stress, the Reynolds shear stress, and the velocity profiles along normal lines of smooth boundary may be determined. This paper is a continuous effort to investigate depth-average shear stress and velocity in rough channels. Equations of the depth-averaged shear stress in typical open channels have been derived based on a theoretical relation between the depth-averaged shear stress and boundary shear stress. Equation of depth mean velocity in a rough channel is also obtained and the effects of water surface (or dip phenomenon) and roughness are included. Experimental data available in the literature have been used for verification that shows that the model reasonably agrees with the measured data.
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Acknowledgments
This research is partially supported by an “Open Fund” provided by State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610065, China.
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Information & Authors
Information
Published In
Journal of Hydraulic Engineering
Volume 136 • Issue 11 • November 2010
Pages: 952 - 958
Copyright
© 2010 ASCE.
History
Received: Mar 7, 2009
Accepted: Apr 27, 2010
Published online: Apr 30, 2010
Published in print: Nov 2010
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