Solute Mixing Models for Water-Distribution Pipe Networks
Publication: Journal of Hydraulic Engineering
Volume 134, Issue 9
Abstract
The spreading of solutes or contaminants through water-distribution pipe networks is controlled largely by mixing at pipe junctions where varying flow rates and concentrations can enter the junction. Alternative models of solute mixing within these pipe junctions are presented in this paper. Simple complete-mixing models are discussed along with rigorous computational-fluid-dynamics models based on turbulent Navier–Stokes equations. In addition, a new model that describes the bulk-mixing behavior resulting from different flow rates entering and leaving the junction is developed in this paper. Comparisons with experimental data have confirmed that this bulk-mixing model provides a lower bound to the amount of mixing that can occur within a pipe junction, while the complete-mixing model yields an upper bound. In addition, a simple scaling parameter is used to estimate the actual (intermediate) mixing behavior based on the bounding predictions of the complete-mixing and bulk-mixing models. These simple analytical models can be readily implemented into network-scale models to develop predictions and bounding scenarios of solute transport and water quality in water-distribution systems.
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Acknowledgments
The writer thanks Professor Chris Choi, Ryan Austin, and Pedro Romero-Gomez from the University of Arizona for providing the experimental data in Romero-Gomez et al. (2006) and Sean McKenna, Jerome Wright, and Lee O’rear for providing the experimental data in McKenna et al. (2007). Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company for the United States Department of Energy’s National Nuclear Security Administration under Contract No. DOEDE-AC04-94AL85000.
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Information & Authors
Information
Published In
Journal of Hydraulic Engineering
Volume 134 • Issue 9 • September 2008
Pages: 1236 - 1244
Copyright
© 2008 ASCE.
History
Received: Nov 13, 2006
Accepted: Jan 9, 2008
Published online: Sep 1, 2008
Published in print: Sep 2008
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