Equilibrium molecular dynamics study of heat conduction in octane

Abstract

Fluids are important components in heat transfer systems. Understanding heat conduction in liquids at the atomic level would allow better design of liquids with specific heat transfer properties. However, heat transfer in molecular chain liquids is a complex interplay between heat transfer within a molecule and between molecules. This thesis studies the contribution of each type of atomic interaction to the bulk heat transfer in liquid octane to further the understanding of thermal transport between and within chain molecules in a liquid. The Green-Kubo formula is used to calculate thermal conductivity of liquid octane from equilibrium molecular dynamics, and the total thermal conductivity is split into effective thermal conductivities for the different types of atomic interactions in the system. It is shown that the short carbon backbone of octane does not dominate thermal transport within the system. Instead, the thermal resistance within a molecule is about the same as the resistance between molecules.