Hydraulic Performance of Ski-Jump-Step Energy Dissipater
Publication: Journal of Hydraulic Engineering
Volume 142, Issue 10
Abstract
Considering the limitations of unit discharge for stepped chutes, a ski-jump-step energy dissipater, which is a new type of energy dissipater, is first proposed for increasing the maximum available unit discharges. In this system, preaerations are achieved through jets generated by ski-jumps and further aerations are achieved via aeration basins. It provides fully aerated flows for the stepped chutes with large unit discharges, and the problems caused by high-speed flows like energy dissipation, cavitation, and atomization are well solved. Experimental investigations about hydraulic characteristics of the ski-jump-step energy dissipater were conducted, including the flow regimes, the principle and effectiveness of energy dissipation and the characteristics of the air entrainment and the pressure distribution. Even under conditions of large unit discharges ( on the prototype), results obtained demonstrate energy dissipation as high as 75.8% and air concentrations of at least 3.6% along the whole stepped chute. The method developed herein provides a new approach for energy dissipation in stepped chutes at large discharges.
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Acknowledgments
This research is supported by the National Natural Science Foundation of China (Grant No. 51479057) and the Research Innovation Program for College Graduates of Jiangsu Province (No. 2014B36414).
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Published In
Journal of Hydraulic Engineering
Volume 142 • Issue 10 • October 2016
Copyright
© 2016 American Society of Civil Engineers.
History
Received: Feb 24, 2015
Accepted: Mar 9, 2016
Published online: Jun 9, 2016
Published in print: Oct 1, 2016
Discussion open until: Nov 9, 2016
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