Field Experiment Study of Transient Stratified Flow in an Estuary
Publication: Journal of Engineering Mechanics
Volume 129, Issue 10
Abstract
An experimental study of stratified flow was conducted in this study. An electromagnetic measurement instrument, the S4 current meter, was used in field data collections of salinity and currents in the lower Apalachicola River estuary, Florida. The S4 current meter has an advantage in field deployments for long periods of time due to its preprogrammable capability for automatic data sampling and recording of fluid flow. Time series of surface and bottom salinity and currents obtained from field experiments were used to characterize the stratified flow at the measurement location in the Apalachicola River. Analysis of field data indicated that the river was strongly stratified. The stratification was affected by the upstream river flow and the downstream tidal variations. Stratification was stronger at high tide than at low tide. By removing the tidal signal using low-passing filtering, subtidal salinity, and currents were obtained to investigate the salinity stratification and currents responses to the changes of fresh water input. Subtidal vertical salinity and velocity profiles were presented at different flow conditions. At high flow conditions, both surface and bottom subtidal currents were in the seaward direction. At low flow conditions, the bottom subtidal currents were in the upstream direction due to the strong effects of density gradients. Empirical regression equations were obtained to quantify the effects of river flow on the subtidal salinity and the bottom currents. Regression analysis indicated good linear relationship between subtidal salinity stratification and the bottom currents.
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References
InterOcean Systems, Inc. (2001). S4 Current Meter Family, available at 〈http://www.interoceansystems.com/〉.
Jones, W. K., and Mozo, M. R. (1994). “Apalachicola Bay freshwater needs assessment program, geophysical data collection program.” Water Resources Special Rep. No. 93-5. Northwest Florida Water Management District, Vol. 1.
Lung, W. S. (1993). Water quality modeling, Vol. III: Application to estuaries, CRC, Boca Raton, Fla.
Martin, J. L., and McCutcheon, S. (1999). Hydrodynamics and transport for water quality modeling, CRC, Boca Raton, Fla.
National Ocean Survey (NOS). (2003). NOS Water Level Observation Network, available at 〈http://co-ops.nos.noaa.gov/usmap/html〉.
Officer, C. B. (1976). Physical oceanography of estuaries, Wiley, New York.
Rantz, S. E., et al. (1982). Measurement and computation of stream flow: Vol. 11: Measurement of stage and discharge; and Vol. 2: Computation of discharge, U.S. Geological Survey Water Supply Paper No. 2175, U.S. Governing Printing Office, Washington, D.C.
Thomann, R. V., and Mueller, J. (1987). Principle of surface water quality modeling and control, Harper & Row.
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Copyright © 2003 American Society of Civil Engineers.
History
Received: Dec 14, 2001
Accepted: Oct 16, 2002
Published online: Sep 15, 2003
Published in print: Oct 2003
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