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Related Experiment Video

Updated: Jul 4, 2026

Characterization of Thermal Transport in One-dimensional Solid Materials

Characterization of Thermal Transport in One-dimensional Solid Materials

Published on: January 26, 2014

Nonequilibrium temperature and thermometry in heat-conducting phi4 models.

Wm G Hoover¹, Carol G Hoover

¹Ruby Valley Research Institute, Highway Contract 60, Box 598 Ruby Valley, Nevada 89833, USA.

Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics

|June 4, 2008

Summary

This study explores temperature and thermometry in heat-conducting models. Kinetic temperature, simulated using Nosé-Hoover thermostats, offers the simplest approach to analyzing nonequilibrium heat flows.

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Area of Science:

Thermodynamics
Statistical Mechanics
Computational Physics

Background:

Understanding temperature and thermometry in systems away from equilibrium is crucial for various scientific fields.
Traditional thermodynamic concepts may not fully capture the behavior of nonequilibrium systems.
Simulating heat flow requires accurate methods for defining and measuring temperature.

Purpose of the Study:

To analyze temperature and thermometry in simple nonequilibrium heat-conducting models.
To compare different definitions of temperature, including kinetic and configurational temperatures.
To evaluate the effectiveness of Nosé-Hoover thermostats for simulating nonequilibrium heat flow.

Main Methods:

Analysis of two- and three-dimensional phi4 models.
Investigation of ideal-gas thermometer correspondence to local instantaneous mechanical kinetic temperature.
Application of Nosé-Hoover thermostats for simulating and analyzing nonequilibrium heat flows.

Main Results:

The ideal-gas thermometer accurately represents local instantaneous mechanical kinetic temperature in these models.
Mechanical temperature closely approximates local thermodynamic equilibrium temperature for phi4 models.
Significant discrepancies exist between kinetic temperature and nonlocal configurational temperature.
Neither temperature definition fully aligns with extended irreversible thermodynamics predictions.

Conclusions:

Kinetic temperature, implemented via Nosé-Hoover thermostats, provides the most straightforward method for simulating and understanding nonequilibrium heat flows.
The study highlights the importance of carefully selecting temperature definitions in nonequilibrium simulations.
Further research may explore more advanced thermometry techniques for complex systems.