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The Frequency Domain Thermoreflectance Technique for Thermal Property Measurements
Published on: December 5, 2025
Spatial dependence of viscosity and thermal conductivity through a planar interface
Janka Petravic1, Peter Harrowell
1School of Chemistry, The University of Sydney NSW 2006, Australia.
The Journal of Physical Chemistry. B
|February 10, 2009
Summary
We developed a new algorithm to study solid-liquid interfaces. Shear viscosity increases with wetting, while thermal conductivity decreases near the interface.
Area of Science:
- Materials Science
- Thermodynamics
- Computational Physics
Background:
- Understanding transport properties at solid-liquid interfaces is crucial for various applications.
- Previous studies often simplified interface complexities, limiting accurate predictions.
- The boundary fluctuation theory provides a framework for analyzing interfacial phenomena.
Purpose of the Study:
- To develop a general algorithm for calculating spatial variations in shear viscosity and thermal conductivity.
- To investigate these transport coefficients at an equilibrium solid-liquid interface.
- To analyze the influence of wetting on interfacial transport properties.
Main Methods:
- Utilized the zero-flux version of the boundary fluctuation theory.
- Developed a general algorithm for calculating spatial variations of transport coefficients.
- Simulated an equilibrium interface between a high melting point and a low melting point Lennard-Jones system.
Main Results:
- Transport coefficients deviate from bulk values only within a narrow interfacial layer.
- Observed increased sliding friction with enhanced solid wetting by the liquid.
- Found suppressed thermal conductivity in the interfacial region, independent of wetting.
Conclusions:
- The developed algorithm accurately captures interfacial transport phenomena.
- Wetting significantly impacts shear viscosity but not thermal conductivity at the interface.
- Results provide insights into heat and momentum transfer across solid-liquid boundaries.
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