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Transport in lungs and branched estuaries

Published online by Cambridge University Press:  26 April 2006

Ronald Smith
Ronald Smith
Affiliation:
Mathematical Sciences, Loughborough University, LE11 3TU, UK
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Abstract

Longitudinal mass transport in branched oscillatory flows is greater than in non-branched oscillatory flows. Here a derivation is given of a longitudinal diffusion equation which governs the long-term mass transport when there is perfect synchronism of the flow in adjacent branches. An explicit formula is obtained for the shear dispersion coefficient (effective longitudinal diffusion) when a sinusoidal flow excursion crosses a junction in geometrically self-similar flows with negligible secondary flow. A single junction crossing can be sufficient to double the shear dispersion as compared to an unbranched flow at the same frequency.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 325 , 25 October 1996 , pp. 331 - 355
Copyright
© 1996 Cambridge University Press

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