Normal Depth in Power-Law Channels
Publication: Journal of Hydrologic Engineering
Volume 20, Issue 7
Abstract
A power-law cross section is very versatile and can be used for a number of practical applications. It allows the modeling of natural rivers (channels) and artificial channels. Normal depth is of high practical importance. This depth is used for computing water surface profiles and for the design, operation, and maintenance of open channels. No direct solution is available in the technical literature for normal depth in power-law channels for an arbitrary value of the exponent. For this channel, the normal depth is presently obtained by trial procedures. The main challenge with power-law sections is the calculation of the wetted perimeter. In this study, the wetted perimeter is estimated by calibrating the method of undetermined coefficients, which results in a simple and accurate expression for the wetted perimeter with the exponent arbitrary between the limits 1 and 2 (case of practical interest). Then, this expression is used to develop an accurate direct solution that can be used to calculate the uniform flow depth of open channels with a power-law cross section.
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Acknowledgments
The author gratefully acknowledges the support provided by the Center of Excellence for Evaluation and Rehabilitation of Irrigation and Drainage Networks, University of Tehran.
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Published In
Journal of Hydrologic Engineering
Volume 20 • Issue 7 • July 2015
Copyright
© 2014 American Society of Civil Engineers.
History
Received: Mar 3, 2014
Accepted: Aug 7, 2014
Published online: Sep 5, 2014
Discussion open until: Feb 5, 2015
Published in print: Jul 1, 2015
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