Study of the Free Surface Flow on an Ogee-Crested Fish Bypass
Publication: Journal of Hydraulic Engineering
Volume 134, Issue 8
Abstract
A study of the free surface flow on an ogee-crested fish bypass is presented. The commercial computational fluid dynamics (CFD) code Fluent 6.1 was used to perform the simulations. Structured/unstructured hybrid grids were used to accommodate the complex geometry that included gate slots, flow control gates, and an aeration slot. The volume of fluid (VOF) approach was used to model the water/air interface. The fish bypass exhibits complex free surface features including free nappes and air entrainment from the air slots. Free surface elevations on both sides of the nappe, pressure along the ogee surface, and discharge rating curves were compared against 1:24 experimental data from the laboratory model for different headwater elevations and gate settings. Limited comparison against measured velocities was also performed. Once deemed reliable through validation against experimental data, the computational model was used to analyze the flow field, supplementing the areas of limited experimental data. Though the paper presents the final fish bypass design, CFD was used to guide the design process and provide insight for several variations in the geometry.
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Acknowledgments
The writers greatly appreciate the partial support by Grant County Public Utility District No. 2 of Grant County, Ephrata, Wash.
References
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Information & Authors
Information
Published In
Journal of Hydraulic Engineering
Volume 134 • Issue 8 • August 2008
Pages: 1172 - 1175
Copyright
© 2008 ASCE.
History
Received: Apr 21, 2005
Accepted: Aug 6, 2007
Published online: Aug 1, 2008
Published in print: Aug 2008
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