Self-Aeration and Friction over Rock Chutes in Uniform Flow Conditions
Publication: Journal of Hydraulic Engineering
Volume 136, Issue 11
Abstract
Interaction between the free surface and the bed material in flow over rock chutes under macroroughness conditions leads to a high air entrainment into the flow. The note reports on an experimental study about air diffusion features in the flow over a long rock chute. Air concentration profiles and water depths over a uniform bed material were measured. An empirical equation for the average air concentration in macroroughness condition for steep slopes is proposed. A new Darcy-Weisbach equivalent friction factor for long chutes as a function of the slope and the relative equivalent depth has also been found.
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Information & Authors
Information
Published In
Journal of Hydraulic Engineering
Volume 136 • Issue 11 • November 2010
Pages: 959 - 964
Copyright
© 2010 ASCE.
History
Received: Nov 1, 2008
Accepted: Apr 26, 2010
Published online: Apr 30, 2010
Published in print: Nov 2010
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