Size-dependent thermal conductivity in nanosystems based on non-Fourier heat transfer

Abstract

Based on a phonon hydrodynamic equation, we derive an analytical model to predict the effective thermal conductivity along dielectric thin films or nanowires with smooth wall surface. The model contains only two parameters: bulk thermal conductivity and Knudsen number, no other fitting parameter included. The predictions from the simple model agree approximately with available experimental data in silicon nanostructures and it outperforms other analytical models based on the Boltzmann transport equation. © 2012 American Institute of Physics.