Experimental Study of Flow in a Vortex Drop Shaft
Publication: Journal of Hydraulic Engineering
Volume 132, Issue 1
Abstract
Model experiments were conducted to investigate the performance of a vortex drop structure with a relatively small height to diameter ratio. Detailed measurements of wall pressure and water thickness of annular jet flow were obtained along the vertical drop shaft, and the rate of air entrainment was measured. The results confirmed the high efficiency of energy dissipation in the vortex drop structure even for a relatively small drop height. The air entrainment rate was found to be significant, and good correlation was observed between the rate of air entrainment and the water jet velocity. The one-dimensional frictional free-vortex flow model was extended to include the effects of pressure forces. While the energy loss in the drop shaft can be simulated by correcting the friction factor, both the frictional model and the extended model significantly underpredict the wall pressure.
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Acknowledgment
The writers would like to thank Professor N. Rajaratnam for his helpful advice during the preparation and revision of this paper.
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Information & Authors
Information
Published In
Journal of Hydraulic Engineering
Volume 132 • Issue 1 • January 2006
Pages: 61 - 68
Copyright
© 2006 ASCE.
History
Received: Sep 12, 2002
Accepted: Mar 25, 2005
Published online: Jan 1, 2006
Published in print: Jan 2006
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