Mean Velocity and Entropy in Wide Channel Flows
Publication: Journal of Hydrologic Engineering
Volume 25, Issue 1
Abstract
For decades many authors have used entropy-based models to predict velocity distribution in open channel flows. Such models use maximum and mean velocity in an assigned domain to obtain velocity distribution. However, while the signification of maximum velocity is clear, the use of mean velocity is sometimes misleading. This paper thus clarifies, for the case of wide channel flows, both, the signification and role of mean velocity within certain existing entropy-based models. It also demonstrates, for some widely cited approaches, the need to pay attention to the difference between the expected value of velocity and the average cross-sectional velocity.
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Data Availability Statement
All data, models, and code generated or used during the study appear in the published article.
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Published In
Journal of Hydrologic Engineering
Volume 25 • Issue 1 • January 2020
Copyright
©2019 American Society of Civil Engineers.
History
Received: Jun 14, 2019
Accepted: Aug 27, 2019
Published online: Oct 30, 2019
Published in print: Jan 1, 2020
Discussion open until: Mar 30, 2020
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