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Evolution of Staircase Structures in Diffusive Convection

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Published on: September 5, 2018

Stochastic order parameter dynamics for phase coexistence in heat conduction.

Shin-Ichi Sasa¹, Naoko Nakagawa², Masato Itami³

¹Department of Physics, Kyoto University, Kyoto 606-8502, Japan.

Physical Review. E

|July 17, 2021

Summary

We developed a model for phase coexistence in steady heat conduction. This model predicts interface temperatures deviating from equilibrium, showing superheated ordered or supercooled disordered states near the interface.

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Area of Science:

Thermodynamics
Statistical Mechanics
Condensed Matter Physics

Background:

Phase coexistence is crucial for understanding material properties.
Nonequilibrium steady states present challenges for traditional thermodynamics.
Previous work suggested deviations from equilibrium transition temperatures in heat conduction.

Purpose of the Study:

To propose a stochastic order parameter model for phase coexistence in steady heat conduction.
To derive a variational principle for nonequilibrium steady states.
To investigate interface temperature behavior and its relation to thermal conductivity.

Main Methods:

Stochastic order parameter modeling.
Analysis of stochastic dynamics with a nonequilibrium adiabatic boundary condition.
Derivation of a variational principle for thermodynamic properties.

Main Results:

A variational principle was derived for nonequilibrium steady states.
Interface temperature depends on the relative thermal conductivity of ordered and disordered regions.
Superheated ordered and supercooled disordered states were predicted near the interface.

Conclusions:

The proposed model successfully describes phase coexistence in steady heat conduction.
The findings support extended thermodynamics frameworks for nonequilibrium systems.
The study highlights the emergence of metastable states in driven systems.