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Exact results for sheared polar active suspensions with variable liquid crystalline order
Aurore Loisy1, Anthony P Thompson1, Jens Eggers1
1School of Mathematics, University of Bristol, Bristol BS8 1TW, United Kingdom.
The Journal of Chemical Physics
|March 17, 2019
Summary
This study on confined sheared active polar liquid crystals reveals that asymmetric boundary conditions create a non-zero shear stress at zero strain. This finding is crucial for understanding active matter rheology.
Area of Science:
- Soft Matter Physics
- Rheology
- Active Matter
Background:
- Active polar liquid crystals exhibit unique flow behaviors.
- Understanding the rheological properties of confined active matter is essential.
Purpose of the Study:
- To investigate the shear stress-strain relationship in confined sheared active polar liquid crystals.
- To analyze the impact of polarization magnitude and asymmetric boundary conditions.
Main Methods:
- One-dimensional model of confined sheared active polar liquid crystals.
- Derivation of analytic solutions for polarization, density, and velocity fields.
- Comparison of analytic solutions with numerical simulations.
Main Results:
- A linear shear stress vs. shear strain relationship was observed.
- A non-zero stress at zero strain rate was demonstrated under asymmetric boundary conditions.
- Analytic solutions provide good approximations for finite-size systems.
Conclusions:
- Asymmetric boundary conditions induce spontaneous stress in active polar liquid crystals.
- The system exhibits non-trivial rheological behavior beyond simple elasticity or viscosity.
- The findings contribute to the theoretical framework of active matter hydrodynamics.
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