Infrared thermography for estimating the thermal conductivity augmentation of polymeric nanocomposites
Debora C. Moreira, Mariana C.O. Telles, Leandro A. Sphaier and Luiz Carlos S. Nunes
The thermal conductivity augmentation in epoxy nanocomposites filled with metal oxides nanoparticles has been investigated. Steady state temperature fields were recorded by an infrared camera in a simple experimental setup. The problem was handled using a heat transfer fin model and theoretical solutions were adjusted to the experimental data in order to estimate the thermal intensification of the epoxy resin by the addition of alumina and copper oxide nanoparticles. Due to relatively high Biot number values, enhanced lumped formulations were employed, since they provide more accurate results without requiring an elaborate heat conduction formulation. Correlations for estimating the convective heat transfer coefficient were employed, in order to assess the thermal conductivity of the samples, and it was observed that this coefficient has a strong influence on the results. In addition, the obtained results were compared with previous data acquired from a commercially available thermal conductivity meter and some differences between them were observed. The thermal intensification tends to smaller values than previously observed for higher loaded nanocomposites, however, the thermal conductivity values of higher loaded nanocomposites are closer to previous data than for low concentrated samples. Despite these discrepancies, the proposed methodology is a promising way to estimate the thermal conductivity augmentation of polymeric nanocomposites.
Keywords: Fin model, Improved lumped, Thermography, Epoxy, Alumina nanoparticle,
Cuo nanoparticle, Thermal conductivity, Heat conduction, Steady State.