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A simple microswimmer model inspired by the general equation for nonequilibrium reversible-irreversible coupling
Andrés Córdoba1, Jay D Schieber2, Tsutomu Indei3
1Department of Chemical Engineering, Universidad de Concepción, Concepción 4030000, Chile.
The Journal of Chemical Physics
|March 9, 2021
Summary
A new mean-field model describes Janus microswimmers using nonequilibrium thermodynamics. This model shows ballistic motion at high reactant concentrations, consistent with the second law of thermodynamics.
Area of Science:
- Statistical Mechanics
- Soft Matter Physics
- Chemical Physics
Background:
- Microswimmers are key to understanding self-propulsion in complex fluids.
- Nonequilibrium thermodynamics governs systems with chemical reactions.
- The general equation for nonequilibrium reversible-irreversible coupling (GENERIC) framework provides a rigorous approach to these systems.
Purpose of the Study:
- To develop a simplified mean-field model for a Janus microswimmer.
- To investigate the dynamics of a microswimmer inspired by polymer solutions and chemical reactions.
- To analyze the mean-squared displacement (MSD) and orientational correlations.
Main Methods:
- Adaptation of the GENERIC framework for multi-component fluids.
- Development of a mean-field model using a polymer dumbbell with a catalytic bead.
- Analysis of the swimmer's center-of-mass MSD and orientation-displacement correlations.
Main Results:
- The Janus microswimmer model exhibits ballistic behavior in its MSD at high reactant concentrations.
- Ballistic motion correlates with the maximization of cross-correlations between swimmer orientation and displacement.
- The model adheres to the second law of thermodynamics, ensuring positive entropy generation.
Conclusions:
- The developed mean-field model offers a simplified yet thermodynamically consistent description of Janus microswimmers.
- The findings link microswimmer dynamics to reactant concentration and orientational behavior.
- This work provides a foundation for further theoretical and experimental studies on active matter in reactive environments.
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