Baffle-Drop Structure Design Relationships
Publication: Journal of Hydraulic Engineering
Volume 139, Issue 9
Abstract
A baffle-drop structure is a flow conveyance structure that can be used for transport of urban storm water down to underground storage tunnels. The water cascades down the structure from baffle to baffle and plunges into a pool at the bottom from where it is conveyed to the tunnel through an adit. The structure has been used successfully in a limited number of urban drainage schemes. However, its hydraulics and air entrainment characteristics are not fully understood. Using a series of laboratory experiments, an analysis has been tested and validated that may be used for design. The analysis provides a dimensionless relationship between key variables, including design discharge, shaft diameter, baffle spacing, and position of a vertical wall dividing the shaft in a dry and a wet portion. Using this relationship the shaft can be designed to maintain atmospheric pressure throughout its height with little or no air being entrained into the tunnel.
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Acknowledgments
This paper is based in part on results of laboratory tests conducted at IIHR-Hydroscience and Engineering for the Regional Municipality of York, the Northeast Ohio Regional Sewer District, and the City of Indianapolis.
References
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Information & Authors
Information
Published In
Journal of Hydraulic Engineering
Volume 139 • Issue 9 • September 2013
Pages: 995 - 1002
Copyright
© 2013 American Society of Civil Engineers.
History
Received: May 10, 2012
Accepted: Mar 20, 2013
Published online: Mar 22, 2013
Discussion open until: Aug 22, 2013
Published in print: Sep 1, 2013
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