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Numerical Test of the Onsager Relations in a Driven System.
Xipeng Wang1, Jure Dobnikar2, Daan Frenkel3
1Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
Physical Review Letters
|December 23, 2022
Summary
This study numerically validates Onsager reciprocity relations in nonequilibrium steady states. The findings extend the applicability of these thermodynamic relations to driven and active systems.
Area of Science:
- Thermodynamics
- Statistical Mechanics
- Computational Physics
Background:
- Onsager reciprocity relations are fundamental in irreversible thermodynamics.
- Their applicability beyond equilibrium and time-reversal symmetry is an open question.
- Nonequilibrium steady states offer a platform to test these relations.
Purpose of the Study:
- To test the validity of Onsager reciprocity relations in a nonequilibrium steady state.
- To investigate the behavior of surface-coupled diffusive and bulk fluxes.
- To explore the applicability of Onsager relations in systems with broken time-reversal symmetry.
Main Methods:
- Numerical simulations of a two-species mixture in a channel.
- Independent tuning of species-wall friction using different collision kinematics (bounce-back or specular).
- Perturbation of a nonequilibrium steady state to observe flux responses.
Main Results:
- Onsager reciprocity relations are obeyed in the linear regime.
- Validity confirmed even in the bounce-back collision case, which lacks time-reversal symmetry.
- Diffusio-capillary transport was observed when species had different temperatures in the bounce-back case.
Conclusions:
- Provides numerical evidence for the broader applicability of Onsager relations.
- Suggests relevance of Onsager relations for transport in active and driven systems.
- Demonstrates the robustness of Onsager relations beyond their original thermodynamic context.
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