Salinity-Induced Density Stratification in Near-Laminar Open-Channel Flows
Publication: Journal of Hydraulic Engineering
Volume 130, Issue 12
Abstract
Salt tracer experiments are a cost-effective tool widely used in studies of flow and transport in free surface flows. Whereas in a large majority of rivers and streams, fully turbulent conditions achieve rapid vertical mixing of injected tracers, this is not necessarily the case with very low Reynolds number flows as encountered e.g., in wetland ponds. There, often laminar to near-laminar transitional flow regimes prevail, and the fact that solutions of elevated salinity are distinctly heavier than water may result in the development of stable density layers, trapping part of the salt tracer and distorting the breakthrough curve recorded at the outlet. In this study, the conditions under which density stratification develops due to salt injection are analyzed, and a criterion is presented which permits an intended salt tracer experiment to be judged at the planning stage already.
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Published In
Journal of Hydraulic Engineering
Volume 130 • Issue 12 • December 2004
Pages: 1206 - 1210
Copyright
Copyright © 2004 ASCE.
History
Published online: Nov 15, 2004
Published in print: Dec 2004
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