Energy Dissipation down a Stepped Spillway with Nonuniform Step Heights
Publication: Journal of Hydraulic Engineering
Volume 137, Issue 11
Abstract
Although most stepped spillway–design guidelines were developed for uniform step heights, a nonuniform stepped design might be a practical alternative in some cases. A physical study was conducted in a moderate slope-stepped chute (1V:2H) and five stepped configurations were tested for . Detailed air-water flow measurements were performed for each configuration and the results were compared in terms of flow patterns, energy dissipation, and flow resistance. The basic findings showed minor differences between all configurations and indicated that the rate of energy dissipation was about the same for uniform and nonuniform stepped configurations. But the observations suggested that the nonuniform stepped configurations might induce some flow instabilities for smaller flow rates.
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Acknowledgments
The writers thank Dr. Jorge Matos (IST Lisbon) for his valuable comments. The financial support of the Australian Research Council (Grant ARCDP0878922) is acknowledged.
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© 2011 American Society of Civil Engineers.
History
Received: Dec 16, 2010
Accepted: May 10, 2011
Published online: May 12, 2011
Published in print: Nov 1, 2011
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