MD Simulations of Nanoparticle Thermal Conductivity and Nanoscale Thermal Contact Resistance

The rapid progress and development of the synthesis and processing of materials with structures having nanometer length scales has created a demand for greater scientific understanding of thermal transport in nanoscale devices. Molecular dynamics (MD) simulations are emerging as a powerful tool for studying thermal conductance and phonon scattering in nanoscale objects. A thermal conduction model for spherical nanoparticles was constructed for non-equilibrium molecular dynamic (NEMD) simulations to investigate variations of the nanoparticle thermal conductivity with particle size. The results show that the nanoparticle thermal conductivity is smaller than the bulk value and that of a thin film with a thickness equal to the particle radius for the same boundary conditions. Another thermal conduction model was constructed to investigate the micro thermal contact resistance variations for various contact scenarios. These results show that the thermal contact resistance is a large part of the conduction resistance that decreases with increasing contact area and increases with increasing contact layer thickness.