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Updated: Oct 16, 2025
08:01
The Diffusion of Passive Tracers in Laminar Shear Flow
Published on: May 1, 2018
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Shear flow of active matter in thin channels
M Carme Calderer1, Dmitry Golovaty2, Lingxing Yao2
1School of Mathematics, University of Minnesota, Minneapolis, Minnesota 55442, USA.
Physical Review. E
|October 16, 2021
Summary
This study analyzes active filament flow in channels using liquid crystal theory. Contractile filaments exhibit complex behavior and sensitivity to flow parameters, suggesting potential biological relevance.
Area of Science:
- Physics
- Soft Matter Physics
- Fluid Dynamics
Background:
- Active filaments, such as cytoskeletal networks, drive motion and deformation in biological systems.
- Understanding their collective behavior in confined geometries is crucial for cell mechanics and biomaterial design.
Purpose of the Study:
- To investigate the shear flow dynamics of confined active filaments, distinguishing between extensile and contractile types.
- To analyze the stability of these flows under varying system parameters using the Ericksen-Leslie equations.
Main Methods:
- Application of the Ericksen-Leslie equations for liquid crystal flow, incorporating an activity source term.
- Dimensionless analysis using Ericksen, activity, and Reynolds numbers, and channel aspect ratio as key parameters.
- Normal mode stability analysis of the base shear flow.
Main Results:
- Comprehensive stability analysis for both extensile and contractile filaments.
- Extensile filaments show instability at a positive activity threshold.
- Contractile filaments display complex behavior at low activity, sensitive to Reynolds number, hinting at plasticity and phase transitions.
Conclusions:
- The study provides a detailed map of stability for active filament flows in channels.
- Findings for extensile filaments align with experimental observations in confined systems.
- The complex dynamics of contractile filaments suggest potential for novel biomaterial properties and biological process modeling.
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