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Updated: Apr 15, 2026
05:20
Characterization of Thermal Transport in One-dimensional Solid Materials
Published on: January 26, 2014
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Scaling laws and bulk-boundary decoupling in heat flow
Jesús J del Pozo1, Pedro L Garrido1, Pablo I Hurtado1
1Institute Carlos I for Theoretical and Computational Physics and Departamento de Electromagnetismo y Física de la Materia, Universidad de Granada, 18071 Granada, Spain.
Summary
Fluids driven out of equilibrium exhibit simple scaling laws, even far from equilibrium. These findings confirm Fourier's law validity in nonlinear regimes and reveal robust scaling in finite-sized systems.
Area of Science:
- Thermodynamics
- Fluid Dynamics
- Statistical Mechanics
Background:
- Macroscopic laws govern fluid behavior when driven out of equilibrium by temperature gradients.
- Fluids develop nontrivial, inhomogeneous structures under such conditions.
Purpose of the Study:
- To investigate the scaling laws governing fluid structure far from equilibrium.
- To determine the validity of Fourier's law in nonlinear thermal regimes.
- To explore the influence of finite-size effects on these scaling laws.
Main Methods:
- Extensive simulations of hard disk fluids.
- Analysis of fluid structure under strong temperature gradients.
- Investigation of bulk-boundary decoupling mechanisms.
Main Results:
- Fluid structure obeys simple scaling laws far from equilibrium, provided local equilibrium and Fourier's law hold.
- Fourier's law remains valid in highly nonlinear regimes, with corrections absorbed into a nonlinear conductivity functional.
- Scaling laws are robust against strong finite-size effects, indicating a bulk-boundary decoupling mechanism.
Conclusions:
- Macroscopic laws, including Fourier's law, are enforced on the bulk of finite-sized fluids.
- The observed robustness allows for the measurement of marginal anomalies in heat conductivity.
- The study provides insights into fluid behavior under extreme nonequilibrium conditions.
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