Dynamics of Air Flow in Sewer Conduit Headspace
Publication: Journal of Hydraulic Engineering
Volume 132, Issue 8
Abstract
Pressurization in sanitary sewer conduit atmosphere is modeled using computational fluid dynamics techniques. The modeling approach considers both turbulent and laminar flow regimes. The turbulent model takes into consideration the turbulence-driven secondary currents associated with the sewer headspace and hence the Reynolds equations governing the air flow field are closed with an anisotropic closure model which comprises the use of the eddy viscosity concept for the turbulent shear stresses and semiempirical relations for the turbulent normal stresses. The resulting formulations are numerically integrated. The turbulent model outputs are verified with experimental data reported in the literature. Satisfactory agreement is obtained between numerical simulations and experimental data. Mathematical formulas and curves as functions of longitudinal pressure gradient, wastewater velocity, and sewer headspace geometry are developed for the cross-sectional average streamwise velocity.
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Acknowledgments
The writers gratefully acknowledge financial support from the Natural Sciences and Engineering Research Council of Canada (NSERC) through a research grant to the second writer and the University of Alberta Research Assistantship to the first writer. They are also grateful to Dr. M. Sterling of the University of Birmingham for providing them with his wind tunnel data.
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Information & Authors
Information
Published In
Journal of Hydraulic Engineering
Volume 132 • Issue 8 • August 2006
Pages: 791 - 799
Copyright
© 2006 ASCE.
History
Received: Oct 20, 2004
Accepted: Nov 9, 2005
Published online: Aug 1, 2006
Published in print: Aug 2006
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