Modeling Depth-Averaged Velocity and Boundary Shear Stress in Rectangular Compound Channels with Secondary Flows
Publication: Journal of Hydraulic Engineering
Volume 139, Issue 1
Abstract
The depth-averaged equation of flow in a rectangular compound channel with secondary flows is established by analyzing the forces acting on the elemental water body and using Newton’s second law. The analytical solution to the transverse variation of depth-averaged velocity is presented that includes the effects of lateral momentum transfer and secondary flow in addition to bed friction. Different forms of boundary conditions at the internal wall between the rectangular main channel and the adjoining floodplain are presented. A comparison with the published experimental data demonstrates that the present model is capable of predicting the distributions of depth-averaged velocity and boundary shear stress. The results also indicate that the secondary flow and boundary conditions have influences on them. Finally, the key parameters in the model, such as the Darcy–Weisbach coefficient, the momentum transfer coefficient, and the secondary flow coefficient are also discussed and analyzed.
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Acknowledgments
The authors gratefully acknowledge the assistance of Professor Donald W. Knight at the University of Birmingham, U.K., who provided the experimental data at <www.flowdata.bham.ac.uk>. The authors gratefully acknowledge the support of the Foundation for the Author of National Excellent Doctoral Dissertation of China (No. 201051) and the National Natural Scientific Foundation of China (No. 11072161 and No. 50709021). The authors are also grateful to the anonymous reviewers for their very helpful comments on this paper.
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Information & Authors
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Published In
Journal of Hydraulic Engineering
Volume 139 • Issue 1 • January 2013
Pages: 76 - 83
Copyright
© 2013 American Society of Civil Engineers.
History
Received: Jun 13, 2011
Accepted: May 30, 2012
Published online: Jul 23, 2012
Published in print: Jan 1, 2013
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