Prediction of Flow-Regime Transition over a Stepped Channel
Publication: Journal of Irrigation and Drainage Engineering
Volume 145, Issue 7
Abstract
For the hydraulic design of a stepped channel, it is crucial to estimate the limit of flow regimes. Step flow in the quasi-uniform region of a stepped channel is analyzed theoretically in this paper. The present work adopts a flow-regime criterion and some assumptions from a method from the literature, a specific energy equation is established, and a weak assumption from the literature is modified to determine the flow conditions in and out of the control volume (CV). A pragmatic method is therefore provided to predict the onset of skimming flow in the quasi-uniform region, and its accuracy is examined through comparison with data from two experimental tests and previous studies.
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Acknowledgments
This research is supported by the National Natural Science Foundation of China (Grant No. 51779081), the Fundamental Research Funds for the Central Universities (No. 2017B622X14), and the Postgraduate Research & Practice Innovation Program of Jiangsu Province (No. KYCX17_0433).
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Published In
Journal of Irrigation and Drainage Engineering
Volume 145 • Issue 7 • July 2019
Copyright
©2019 American Society of Civil Engineers.
History
Received: Oct 12, 2018
Accepted: Jan 30, 2019
Published online: Apr 24, 2019
Published in print: Jul 1, 2019
Discussion open until: Sep 24, 2019
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