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In this paper, we investigate a sink-driven three-layer flow in a radial Hele-Shaw cell. The three fluids are of different viscosities, with one fluid occupying an annulus-like domain, forming two interfaces with the other two fluids. Using a boundary integral method and a semi-implicit time stepping scheme, we alleviate the numerical stiffness in updating the interfaces and achieve spectral accuracy in space. The interaction between the two interfaces introduces novel dynamics leading to rich pattern formation phenomena, manifested by two typical events: either one of the two interfaces reaches the sink faster than the other (forming cusp-like morphology), or they come very close to each other (suggesting a possibility of interface merging). In particular, the inner interface can be wrapped by the other to have both scenarios. We find that multiple parameters contribute to the dynamics, including the width of the annular region, the location of the sink, and the mobilities of the fluids.
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Flows of a nonequilibrated aqueous two-phase system in a microchannel
Flows of nonequilibrated aqueous two-phase systems may result in the formation of a 3-dimensional flow field, due to a gradient in tension across the boundary of the two phases.
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- Award ID(s):
- 2011750
- PAR ID:
- 10508948
- Publisher / Repository:
- Soft Matter
- Date Published:
- Journal Name:
- Soft Matter
- Volume:
- 19
- Issue:
- 20
- ISSN:
- 1744-683X
- Page Range / eLocation ID:
- 3551 to 3561
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/D3SM00233K
