With technological advancements and ever-growing competition, the need for Carbon Nanotubes (CNTs) is now greater than ever. Some engineering applications for CNTs are sensors, field emission devices, energy storage, composite materials, and heat dissipation sinks. Heat transfer applications like the heat dissipation in computers remain a challenge. It has been theoretically proven that the thermal conductivity of Multiwalled Carbon Nanotubes (MWCNTs) can reach 3000 W/mK. Experimental measurements, however, have shown much lower values, although higher than those of carbon micro fibers and polymeric matrices. For polymeric composite materials, in-plane thermal conductivity is governed by the carbon fibers but the out of plane conductivity is dominated by the polymeric matrix. Using aligned CNT arrays in the transverse direction is expected to substantially increase the thermal conductivity. In this thesis a study was conducted to better understand heat conduction in CNT arrays and quantify their thermal conductivity.
A method was devised to measure the thermal conductivity of carbon nanotube arrays based on Fourier’s law. The method relied on using a strain gage as a heater and maintaining a steady state one dimensional flow. Heat was provided with a power source and thermocouples were placed at various points on the sample and connected to a thermocouple reader. Various parameters that affect the thermal conductivity of CNTs are the alignment, density, chirality, functionalization, and interface resistance. Interface resistance is one of the major parameters that affects the thermal conductivity. This thesis presents the results of a study on the effect of interface materials, array density and height on the thermal conductivity of CNT arrays.