Scaling of Velocity Profiles for Depth-Limited Open Channel Flows over Simulated Rigid Vegetation
Publication: Journal of Hydraulic Engineering
Volume 138, Issue 8
Abstract
Using the plane mixing layer analogy, a length scale is proposed to normalize velocity profiles for vegetated open channel flows. The new scaling is an improvement over those based on the logarithmic, velocity-defect, and power laws in collapsing the velocity profiles, which include measurements conducted in this study and also those reported in the literature for a variety of flow and vegetation configurations. An eddy viscosity model is also developed to justify the scaling argument. This study is limited to rigid vegetation submerged in depth-limited flows, in which the flow depth is no greater than twice the vegetation height.
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Acknowledgments
This research is supported partially by the Maritime Research Centre, Nanyang Technological University, Singapore. The authors would like to acknowledge the valuable comments by Adel Emadzadeh and Kuifeng Zhao. Songdong Shao also acknowledges the support of Royal Society International Travel Grants 2010/R4 Travel for Collaboration (TG102591). Nian-Sheng Cheng and Songdong Shao greatly appreciate the support of the Open Fund provided by the State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu, P.R. China.
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Published In
Journal of Hydraulic Engineering
Volume 138 • Issue 8 • August 2012
Pages: 673 - 683
Copyright
© 2012. American Society of Civil Engineers.
History
Received: Jul 17, 2011
Accepted: Jan 18, 2012
Published online: Jan 20, 2012
Published in print: Aug 1, 2012
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