Microfluidic converging-diverging channels optimised for homogeneous extensional deformation

K. Zografos, F. Pimenta, M. A. Alves, M. S. N. Oliveira

Research output: Contribution to journalArticle

16 Citations (Scopus)

Abstract

In this work we optimise microfluidic converging/diverging geometries in order to produce constant strain-rates along the centreline of the flow, for performing studies under homogeneous extension. The design is examined for both two-dimensional and three-dimensional flows where the effects of aspect ratio and dimensionless contraction length are investigated. Initially, pressure driven flows of Newtonian fluids under creeping flow conditions are considered, which is a reasonable approximation in microfluidics, and the limits of the applicability of the design in terms of Reynolds numbers are investigated. The optimised geometry is then used for studying the flow of viscoelastic fluids and the practical limitations in terms of Weissenberg number are reported. Furthermore, the optimisation strategy is also applied for electro-osmotic driven flows, where the development of a plug-like velocity profile allows for a wider region of homogeneous extensional deformation in the flow field.
LanguageEnglish
Article number043508
Number of pages21
JournalBiomicrofluidics
Volume10
Issue number4
Early online date5 Jul 2016
DOIs
Publication statusPublished - 31 Jul 2016

Fingerprint

Microfluidics
Newtonian flow
Geometry
Flow of fluids
Aspect ratio
Strain rate
Flow fields
Reynolds number
Pressure
three dimensional flow
Newtonian fluids
plugs
geometry
strain rate
contraction
aspect ratio
flow distribution
velocity distribution
optimization
fluids

Keywords

  • extensional flow
  • electro-osmotic flow
  • viscoelastic fluids
  • diverging channels
  • converging channels
  • optimisation

Cite this

@article{a7cbad03711d4f3bbc02d8dfa83d7814,
title = "Microfluidic converging-diverging channels optimised for homogeneous extensional deformation",
abstract = "In this work we optimise microfluidic converging/diverging geometries in order to produce constant strain-rates along the centreline of the flow, for performing studies under homogeneous extension. The design is examined for both two-dimensional and three-dimensional flows where the effects of aspect ratio and dimensionless contraction length are investigated. Initially, pressure driven flows of Newtonian fluids under creeping flow conditions are considered, which is a reasonable approximation in microfluidics, and the limits of the applicability of the design in terms of Reynolds numbers are investigated. The optimised geometry is then used for studying the flow of viscoelastic fluids and the practical limitations in terms of Weissenberg number are reported. Furthermore, the optimisation strategy is also applied for electro-osmotic driven flows, where the development of a plug-like velocity profile allows for a wider region of homogeneous extensional deformation in the flow field.",
keywords = "extensional flow, electro-osmotic flow, viscoelastic fluids, diverging channels, converging channels, optimisation",
author = "K. Zografos and F. Pimenta and Alves, {M. A.} and Oliveira, {M. S. N.}",
year = "2016",
month = "7",
day = "31",
doi = "10.1063/1.4954814",
language = "English",
volume = "10",
journal = "Biomicrofluidics",
issn = "1932-1058",
number = "4",

}

Microfluidic converging-diverging channels optimised for homogeneous extensional deformation. / Zografos, K.; Pimenta, F.; Alves, M. A.; Oliveira, M. S. N.

In: Biomicrofluidics, Vol. 10, No. 4, 043508, 31.07.2016.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Microfluidic converging-diverging channels optimised for homogeneous extensional deformation

AU - Zografos, K.

AU - Pimenta, F.

AU - Alves, M. A.

AU - Oliveira, M. S. N.

PY - 2016/7/31

Y1 - 2016/7/31

N2 - In this work we optimise microfluidic converging/diverging geometries in order to produce constant strain-rates along the centreline of the flow, for performing studies under homogeneous extension. The design is examined for both two-dimensional and three-dimensional flows where the effects of aspect ratio and dimensionless contraction length are investigated. Initially, pressure driven flows of Newtonian fluids under creeping flow conditions are considered, which is a reasonable approximation in microfluidics, and the limits of the applicability of the design in terms of Reynolds numbers are investigated. The optimised geometry is then used for studying the flow of viscoelastic fluids and the practical limitations in terms of Weissenberg number are reported. Furthermore, the optimisation strategy is also applied for electro-osmotic driven flows, where the development of a plug-like velocity profile allows for a wider region of homogeneous extensional deformation in the flow field.

AB - In this work we optimise microfluidic converging/diverging geometries in order to produce constant strain-rates along the centreline of the flow, for performing studies under homogeneous extension. The design is examined for both two-dimensional and three-dimensional flows where the effects of aspect ratio and dimensionless contraction length are investigated. Initially, pressure driven flows of Newtonian fluids under creeping flow conditions are considered, which is a reasonable approximation in microfluidics, and the limits of the applicability of the design in terms of Reynolds numbers are investigated. The optimised geometry is then used for studying the flow of viscoelastic fluids and the practical limitations in terms of Weissenberg number are reported. Furthermore, the optimisation strategy is also applied for electro-osmotic driven flows, where the development of a plug-like velocity profile allows for a wider region of homogeneous extensional deformation in the flow field.

KW - extensional flow

KW - electro-osmotic flow

KW - viscoelastic fluids

KW - diverging channels

KW - converging channels

KW - optimisation

UR - http://scitation.aip.org/content/aip/journal/bmf/browse

U2 - 10.1063/1.4954814

DO - 10.1063/1.4954814

M3 - Article

VL - 10

JO - Biomicrofluidics

T2 - Biomicrofluidics

JF - Biomicrofluidics

SN - 1932-1058

IS - 4

M1 - 043508

ER -