Numerical Simulation and Assessment of the Effects of Operation and Baffling on a Potable Water Service Reservoir
Publication: Journal of Environmental Engineering
Volume 139, Issue 3
Abstract
A major water-quality concern in a potable water service reservoir is the potential loss of chlorine residual, which is closely related to the flow pattern. In this article, the effects of operation and baffling on the flow pattern and chlorine-concentration distribution in a potable water service reservoir are reported. Using a computational fluid dynamics (CFD) method coupled with dynamic meshes, actual service conditions are mimicked, which have seldom been reported in the literature. First, this article provides an insight into why manipulating the valve located at the inlet can be beneficial in enhancing water quality in the long run. An explanation based on the simulation results suggests that manipulating the valve located at the inlet can lead to the evolution and migration of the vortices in the service reservoir, which would then allow water with prolonged age to flow out of the reservoir. This is significant for the operation of service reservoirs. Second, it explores the possibility of retrofitting a service reservoir with baffle walls to minimize the probability of seriously diminished water quality resulting from poor mixing and excessive aging. Although adding baffle walls in the flow-recirculation regions is found to break up the vortices and thus shorten the flow path, the fluid-velocity magnitude is reduced after flowing past the baffle walls. The outcome of these conflicting effects may eventually lead to a diminished effluent chlorine concentration after adding the baffle walls.
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Acknowledgments
The authors extend appreciation to the Public Utilities Board of Singapore for the support of this research. Special thanks are given to Mr. Gek Hee Tan, Ms. Joyce Lau, Mr. Khee Lin Yeo, Miss Xingxia Chen, and Mr. Kim Hoo Lee for sharing their knowledge and expertise.
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Information & Authors
Information
Published In
Journal of Environmental Engineering
Volume 139 • Issue 3 • March 2013
Pages: 341 - 348
Copyright
© 2013 American Society of Civil Engineers.
History
Received: Feb 1, 2012
Accepted: Jul 25, 2012
Published online: Aug 2, 2012
Published in print: Mar 1, 2013
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