Entropy Theory for Two-Dimensional Velocity Distribution
Publication: Journal of Hydrologic Engineering
Volume 16, Issue 4
Abstract
Assuming time-averaged velocity as a random variable, this study develops an entropy theory for deriving two-dimensional (2D) distribution of velocity in open channels. The theory comprises five parts: (1) Tsallis entropy; (2) principle of maximum entropy (POME); (3) specification of information on velocity in terms of constraints; (4) maximization of entropy; and (5) derivation of the probability distribution of velocity. The entropy theory is then combined with a hypothesis on the cumulative distribution function of velocity in terms of flow depth to derive a 2D velocity distribution. The derived distribution is tested using field as well as laboratory observations reported in the literature and is compared with known velocity distributions. Agreement between velocity values computed using the entropy-based distribution and observed values is found satisfactory. Also, the derived distribution compares favorably with known distributions.
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Information & Authors
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Published In
Journal of Hydrologic Engineering
Volume 16 • Issue 4 • April 2011
Pages: 303 - 315
Copyright
© 2011 American Society of Civil Engineers.
History
Received: Feb 2, 2010
Accepted: Sep 1, 2010
Published online: Sep 7, 2010
Published in print: Apr 1, 2011
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