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05:20
Characterization of Thermal Transport in One-dimensional Solid Materials
Published on: January 26, 2014
A nonequilibrium molecular dynamics method for thermal conductivities based on thermal noise
Takamichi Terao1, Florian Müller-Plathe
1International University Bremen, P.O. Box 750 561, D-28725 Bremen, Germany.
The Journal of Chemical Physics
|April 20, 2005
Summary
A novel nonequilibrium molecular dynamics (NEMD) method efficiently calculates thermal conductivity by utilizing uniform heat sources, simplifying calculations and improving implementation. This approach accurately determined the thermal conductivity of liquid water.
Area of Science:
- Computational physics
- Materials science
- Thermodynamics
Background:
- Calculating thermal conductivity is crucial for material characterization.
- Traditional nonequilibrium molecular dynamics (NEMD) methods face challenges with localized heat sources and fluxes.
- Existing NEMD algorithms often treat system noise as a nuisance factor.
Purpose of the Study:
- To develop a new NEMD method for calculating thermal conductivity.
- To leverage uniform heat sources, including system noise, for improved efficiency.
- To simplify the derivation, analysis, and implementation of NEMD algorithms.
Main Methods:
- Developed a novel NEMD algorithm where the heat sink is localized, and the heat source is uniformly distributed.
- Utilized system noise (from pair force cutoffs or integration errors) as a uniform heat source.
- Circumvented the need for direct energy flux calculations.
Main Results:
- The new NEMD method was successfully tested on the enhanced simple-point charge model for liquid water.
- The method accurately reproduced the known thermal conductivity of this water model (0.81 W m(-1) K(-1)).
- The algorithm demonstrated ease of derivation, analysis, and implementation.
Conclusions:
- The developed NEMD method offers an efficient and simplified approach to thermal conductivity calculations.
- The algorithm's flexibility allows generalization to various heat source/sink configurations.
- This method provides a robust alternative for studying thermal transport in materials.
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