Aeration Characteristics of Ski Jump Jets
Publication: Journal of Hydraulic Engineering
Volume 134, Issue 1
Abstract
Scour downstream of ski jumps may be avoided by jet deflection to an area where the energy dissipation is accomplished. The main purpose of this experimental study was the analysis of the jet air entrainment downstream of a ski jump, both for pure water and preaerated approach flow conditions. A systematic variation of the Froude number and the flow depth in the approach flow channel resulted in a range of discharge characteristics, whereas the geometry of the ski jump was maintained for all tests. The air concentration profile was measured at different locations downstream from the ski jump to evaluate the: (1) jet air concentration distribution; (2) location of minimum air concentration along the mixture flow jet and development of the minimum and the cross-sectional average air concentrations; (3) jet trajectories; and (4) process of air entrainment characteristics and jet disintegration. The results demonstrate the significant effect of the approach flow Froude number, the approach flow depth, and of preaeration on jet disintegration.
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Acknowledgments
The second writer was supported by the Swiss National Science Foundation, Grant No. NSF-CH200021-101548/1.
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Information & Authors
Information
Published In
Journal of Hydraulic Engineering
Volume 134 • Issue 1 • January 2008
Pages: 90 - 97
Copyright
© 2008 ASCE.
History
Received: Nov 22, 2006
Accepted: May 25, 2007
Published online: Jan 1, 2008
Published in print: Jan 2008
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