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Published on: March 13, 2016
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Nematohydrodynamics for colloidal self-assembly and transport phenomena
Sourav Mondal1, Apala Majumdar2, Ian M Griffiths1
1Mathematical Institute, University of Oxford, Oxford OX2 6GG, UK.
Journal of Colloid and Interface Science
|September 1, 2018
Summary
Colloidal particles in nematic liquid crystals (NLCs) behave uniquely due to elastic stresses. This study reveals critical forces and self-assembly mechanisms for particle separation in NLC microfluidics.
Area of Science:
- Physics
- Materials Science
- Fluid Dynamics
Background:
- Colloidal particle behavior differs significantly in nematic liquid crystals (NLCs) compared to isotropic media.
- Nematic-induced elastic stresses compete with viscous forces, altering particle dynamics.
Purpose of the Study:
- To mathematically analyze particle behavior in an NLC microfluidic channel.
- To investigate the interplay of viscous and elastic forces on colloidal particles.
Main Methods:
- Utilized the continuum Beris-Edwards framework coupled with Navier-Stokes equations.
- Imposed strong homeotropic anchoring on channel walls and weak anchoring on particle surfaces.
Main Results:
- Identified a critical channel location where perpendicular forces on individual particles balance.
- Demonstrated that multi-particle aggregation outcomes are independent of initial configurations.
- Observed distinct pathways to equilibrium for particle aggregation.
Conclusions:
- Uncovered novel mechanisms for particle separation in NLCs.
- Revealed new routes for achieving self-assembly of colloidal particles.
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