Liquid-gas transitions in steady heat conduction

TL;DR

This paper investigates liquid-gas phase transitions in steady heat conduction systems, revealing volume discontinuities and stable super-cooled gas states near the transition point under constant pressure and linear response conditions.

Contribution

It introduces a thermodynamic equality with a global temperature to predict volume changes and characterizes interface formation and super-cooled states in heat conduction systems.

Findings

Volume discontinuity at the transition point.

Stable super-cooled gas near the interface.

Global temperature equality predicts transition behavior.

Abstract

We study liquid-gas transitions of heat conduction systems in contact with two heat baths under constant pressure in the linear response regime. On the basis of local equilibrium thermodynamics, we propose an equality with a global temperature, which determines the volume near the equilibrium liquid-gas transition. We find that the formation of the liquid-gas interface is accompanied by a discontinuous change in the volume when increasing the mean temperature of the baths. A super-cooled gas near the interface is observed as a stable steady state.