Nonlocal Effects and Slip Heat Flow in Nanolayers

Area of Science:

• Nanoscale heat transfer
• Macroscopic physical modeling

Background:

• The Guyer-Krumhansl (G-K) equation is a key macroscopic model for nanoscale heat transport.
• Existing models often lack precision in accounting for boundary interactions.

Purpose of the Study:

• To modify the G-K equation by incorporating a new nonlocal characteristic length.
• To develop a slip heat flux boundary condition considering heat carrier-boundary interactions and mean free path.
• To obtain analytical solutions for heat flux and thermal conductivity in 2D nanolayers.

Main Methods:

• Modification of the nonlocal term in the G-K equation.
• Development of a slip heat flux boundary condition.
• Derivation of analytical solutions for heat flux and in-plane thermal conductivity.
• Validation using Direct Simulation Monte Carlo (DSMC) and experimental data.

Main Results:

• A modified G-K equation with a new nonlocal characteristic length and slip boundary condition was established.
• Analytical solutions for heat flux and thermal conductivity in 2D nanolayers were derived.
• The model's predictions showed excellent agreement with DSMC simulations for argon gas nanolayers and experimental data for silicon thin layers.

Conclusions:

• The proposed modifications enhance the G-K equation's accuracy for nanoscale heat transport.
• The findings offer theoretical support for applying the G-K equation in predicting nanolayer thermal properties.
• This work advances the understanding of heat carriers-boundaries interactions in nanostructures.