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Geometry-Dependent Elastic Flow Dynamics in Micropillar Arrays

Ström, Oskar E. LU orcid ; Beech, Jason P. LU and Tegenfeldt, Jonas O. LU orcid (2024) In Micromachines 15(2).
Abstract

Regular device-scale DNA waves for high DNA concentrations and flow velocities have been shown to emerge in quadratic micropillar arrays with potentially strong relevance for a wide range of microfluidic applications. Hexagonal arrays constitute another geometry that is especially relevant for the microfluidic pulsed-field separation of DNA. Here, we report on the differences at the micro and macroscopic scales between the resulting wave patterns for these two regular array geometries and one disordered array geometry. In contrast to the large-scale regular waves visible in the quadratic array, in the hexagonal arrays, waves occur in a device-scale disordered zig-zag pattern with fluctuations on a much smaller scale. We connect the... (More)

Regular device-scale DNA waves for high DNA concentrations and flow velocities have been shown to emerge in quadratic micropillar arrays with potentially strong relevance for a wide range of microfluidic applications. Hexagonal arrays constitute another geometry that is especially relevant for the microfluidic pulsed-field separation of DNA. Here, we report on the differences at the micro and macroscopic scales between the resulting wave patterns for these two regular array geometries and one disordered array geometry. In contrast to the large-scale regular waves visible in the quadratic array, in the hexagonal arrays, waves occur in a device-scale disordered zig-zag pattern with fluctuations on a much smaller scale. We connect the large-scale pattern to the microscopic flow and observe flow synchronization that switches between two directions for both the quadratic and hexagonal arrays. We show the importance of order using the disordered array, where steady-state stationary and highly fluctuating flow states persist in seemingly random locations across the array. We compare the flow dynamics of the arrays to that in a device with sparsely distributed pillars. Here, we observe similar vortex shedding, which is clearly observable in the quadratic and disordered arrays. However, the shedding of these vortices couples only in the flow direction and not laterally as in the dense, ordered arrays. We believe that our findings will contribute to the understanding of elastic flow dynamics in pillar arrays, helping us elucidate the fundamental principles of non-Newtonian fluid flow in complex environments as well as supporting applications in engineering involving e.g., transport, sorting, and mixing of complex fluids.

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Please use this url to cite or link to this publication:
author
; and
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
DNA waves, elastic turbulence, geometry, microfluidics, micropillar arrays, polarization, polymer solutions, porous media
in
Micromachines
volume
15
issue
2
article number
268
publisher
MDPI AG
external identifiers
  • pmid:38398996
  • scopus:85185884639
ISSN
2072-666X
DOI
10.3390/mi15020268
language
English
LU publication?
yes
additional info
Publisher Copyright: © 2024 by the authors.
id
7d3a0aa4-2edd-4e41-bfc2-d7436245b6d8
date added to LUP
2024-03-20 10:36:38
date last changed
2024-04-17 10:02:47
@article{7d3a0aa4-2edd-4e41-bfc2-d7436245b6d8,
  abstract     = {{<p>Regular device-scale DNA waves for high DNA concentrations and flow velocities have been shown to emerge in quadratic micropillar arrays with potentially strong relevance for a wide range of microfluidic applications. Hexagonal arrays constitute another geometry that is especially relevant for the microfluidic pulsed-field separation of DNA. Here, we report on the differences at the micro and macroscopic scales between the resulting wave patterns for these two regular array geometries and one disordered array geometry. In contrast to the large-scale regular waves visible in the quadratic array, in the hexagonal arrays, waves occur in a device-scale disordered zig-zag pattern with fluctuations on a much smaller scale. We connect the large-scale pattern to the microscopic flow and observe flow synchronization that switches between two directions for both the quadratic and hexagonal arrays. We show the importance of order using the disordered array, where steady-state stationary and highly fluctuating flow states persist in seemingly random locations across the array. We compare the flow dynamics of the arrays to that in a device with sparsely distributed pillars. Here, we observe similar vortex shedding, which is clearly observable in the quadratic and disordered arrays. However, the shedding of these vortices couples only in the flow direction and not laterally as in the dense, ordered arrays. We believe that our findings will contribute to the understanding of elastic flow dynamics in pillar arrays, helping us elucidate the fundamental principles of non-Newtonian fluid flow in complex environments as well as supporting applications in engineering involving e.g., transport, sorting, and mixing of complex fluids.</p>}},
  author       = {{Ström, Oskar E. and Beech, Jason P. and Tegenfeldt, Jonas O.}},
  issn         = {{2072-666X}},
  keywords     = {{DNA waves; elastic turbulence; geometry; microfluidics; micropillar arrays; polarization; polymer solutions; porous media}},
  language     = {{eng}},
  month        = {{02}},
  number       = {{2}},
  publisher    = {{MDPI AG}},
  series       = {{Micromachines}},
  title        = {{Geometry-Dependent Elastic Flow Dynamics in Micropillar Arrays}},
  url          = {{http://dx.doi.org/10.3390/mi15020268}},
  doi          = {{10.3390/mi15020268}},
  volume       = {{15}},
  year         = {{2024}},
}