Longitudinal Dispersion Coefficients in Estuary
Publication: Journal of Hydraulic Engineering
Volume 118, Issue 5
Abstract
Field measurements of velocity and salinity on a transverse cross section of a straight reach in the upper Conwy estuary have been used to evaluate the temporal and intratidal variations of the transverse and vertical shear induced components of the longitudinal dispersion coefficient. The results yield clear temporal trends and an element of reproducibility between tides. A comparison with earlier published results for a cross section further downstream in the same estuary suggests that changes in the channel width, cross‐sectional shape, and bends probably contribute significantly to a longitudinal variation of dispersion coefficient values. A comparison of the values of the longitudinal dispersion coefficients with those obtained from a solution of governing transport equations emphasizes the need for a better understanding of the spatial and temporal variation of the values of the vertical and transverse eddy diffusion coefficients.
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Information & Authors
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Published In
Journal of Hydraulic Engineering
Volume 118 • Issue 5 • May 1992
Pages: 718 - 734
Copyright
Copyright © 1992 ASCE.
History
Published online: May 1, 1992
Published in print: May 1992
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