Computational study of nano- and meso-scale size effects on thermal transport

In the era where structures and devices are of the order of a few nanometers, a detailed understanding on the heat carriers in nanostructured devices is required to enable further improvements and advances. In the first portion of this thesis we develop a new methodology using Molecular Dynamics (MD) to determine the thermal conductivity of argon with a modified Leonard Jones potential as a function of the modulation frequency input heat flux. We observe a decrease in the thermal conductivity as the heat transport enters the ballistic regime by an order of magnitude which agrees with some of the recent literature on similar experimental work. We further compare the trends by performing Boltzmann Transport Equation (BTE) simulations. In the second part we analyze the effective medium theory as modified by Minnich and Chen, to understand the size effect of metal particles in non-metal composites. We predict results for a range of materials and sizes, and compare the results using the two temperature model (TTM) and a finite element analysis