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Updated: Jun 20, 2026
11:51
Visually Based Characterization of the Incipient Particle Motion in Regular Substrates: From Laminar to Turbulent Conditions
Published on: February 22, 2018
Active alignment-driven coarsening in confined near-critical fluids
Parameshwaran A1, Bhaskar Sen Gupta1
1Vellore Institute of Technology, Department of Physics, School of Advanced Sciences, Vellore, Tamil Nadu 632014, India.
Physical Review. E
|June 19, 2026
Summary
Activity in confined fluids overcomes arrest. Self-propulsion in active fluids promotes domain merging and complete phase separation, transitioning from diffusive to ballistic growth. This research offers insights into confined active fluid dynamics.
Area of Science:
- Physics
- Soft Matter Physics
- Computational Physics
Background:
- Phase separation in confined systems often leads to kinetically arrested states.
- Understanding active matter dynamics is crucial for various applications.
Purpose of the Study:
- To investigate vapor-liquid phase separation in active fluids under confinement.
- To explore how self-propulsion influences domain morphology and coarsening kinetics.
Main Methods:
- Molecular dynamics simulations of a Lennard-Jones fluid.
- Introduction of Vicsek-type alignment interactions to model activity.
- Analysis of domain morphology, coarsening kinetics, and correlation functions.
Main Results:
- Passive fluids exhibit spinodal decomposition and kinetic arrest in a striped state.
- Activity destabilizes the arrested state, promoting domain mergers and complete separation.
- Late-stage coarsening shows a crossover to ballistic growth (exponent α=2/3).
Conclusions:
- Alignment-induced activity can overcome confinement-driven kinetic arrest.
- Activity significantly alters phase separation dynamics in quasi-one-dimensional systems.
- Provides a framework for understanding phase separation in confined active fluids.
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