Laminar dispersion at high Péclet numbers in finite-length channels : Effects of the near-wall velocity profile and connection with the generalized Leveque problem
(2009) In Physics of Fluids 21(12). p.1-20- Abstract
This article develops the theory of laminar dispersion in finite-length channel flows at high Péclet numbers, completing the classical Taylor-Aris theory which applies for long-term, long-distance properties. It is shown, by means of scaling analysis and invariant reformulation of the moment equations, that solute dispersion in finite length channels is characterized by the occurrence of a new regime, referred to as the convection-dominated transport. In this regime, the properties of the dispersion boundary layer and the values of the scaling exponents controlling the dependence of the moment hierarchy on the Péclet number are determined by the local near-wall behavior of the axial velocity. Specifically, different scaling laws in the... (More)
This article develops the theory of laminar dispersion in finite-length channel flows at high Péclet numbers, completing the classical Taylor-Aris theory which applies for long-term, long-distance properties. It is shown, by means of scaling analysis and invariant reformulation of the moment equations, that solute dispersion in finite length channels is characterized by the occurrence of a new regime, referred to as the convection-dominated transport. In this regime, the properties of the dispersion boundary layer and the values of the scaling exponents controlling the dependence of the moment hierarchy on the Péclet number are determined by the local near-wall behavior of the axial velocity. Specifically, different scaling laws in the behavior of the moment hierarchy occur, depending whether the cross-sectional boundary is smooth or nonsmooth (e.g., presenting corner points or cusps). This phenomenon marks the difference between the dispersion boundary layer and the thermal boundary layer in the classical Leveque problem. Analytical and numerical results are presented for typical channel cross sections in the Stokes regime.
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- author
- Giona, M. ; Adrover, A. ; Cerbelli, S. and Garofalo, F. LU
- publishing date
- 2009-12
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Physics of Fluids
- volume
- 21
- issue
- 12
- article number
- 019911PHF
- pages
- 20 pages
- publisher
- American Institute of Physics (AIP)
- external identifiers
-
- scopus:76249096777
- ISSN
- 1070-6631
- DOI
- 10.1063/1.3263704
- language
- English
- LU publication?
- no
- id
- f79b35cf-119c-4465-883c-7bb6a7402ea0
- date added to LUP
- 2016-06-27 10:09:09
- date last changed
- 2022-01-30 04:47:54
@article{f79b35cf-119c-4465-883c-7bb6a7402ea0,
abstract = {{<p>This article develops the theory of laminar dispersion in finite-length channel flows at high Péclet numbers, completing the classical Taylor-Aris theory which applies for long-term, long-distance properties. It is shown, by means of scaling analysis and invariant reformulation of the moment equations, that solute dispersion in finite length channels is characterized by the occurrence of a new regime, referred to as the convection-dominated transport. In this regime, the properties of the dispersion boundary layer and the values of the scaling exponents controlling the dependence of the moment hierarchy on the Péclet number are determined by the local near-wall behavior of the axial velocity. Specifically, different scaling laws in the behavior of the moment hierarchy occur, depending whether the cross-sectional boundary is smooth or nonsmooth (e.g., presenting corner points or cusps). This phenomenon marks the difference between the dispersion boundary layer and the thermal boundary layer in the classical Leveque problem. Analytical and numerical results are presented for typical channel cross sections in the Stokes regime.</p>}},
author = {{Giona, M. and Adrover, A. and Cerbelli, S. and Garofalo, F.}},
issn = {{1070-6631}},
language = {{eng}},
number = {{12}},
pages = {{1--20}},
publisher = {{American Institute of Physics (AIP)}},
series = {{Physics of Fluids}},
title = {{Laminar dispersion at high Péclet numbers in finite-length channels : Effects of the near-wall velocity profile and connection with the generalized Leveque problem}},
url = {{http://dx.doi.org/10.1063/1.3263704}},
doi = {{10.1063/1.3263704}},
volume = {{21}},
year = {{2009}},
}