Measurement of Apparent Thermal Conductivity of Nano Particles

A new measurement method based on a proprietary, developed at ITL methodology for measurement of thermal conductivity of thin rods is being developed and used in a project aimed at measurement of thermal conductivity of various types of nano particles including single wall carbon nanotubes (SWCNT). The thermal conductivity of nano particles can be determined based on mathematical models of apparent thermal conductivity of mixtures of such particles with liquids. The different mathematical models take into account the shape of particles, their sizes, volume concentration and orientation f the particles inside the mixture. Measurement of apparent thermal conductivity of the prepared mixtures will be conducted using standard well-established methods. For reliable and stable results, very good wetting of the particles by the chosen liquid should be provided. A thorough study of wetting behavior of the SWCNT by liquids will be conducted and the most appropriate liquid will be chosen for experiments. Based on apparent thermal conductivity measurements and the above mathematical models, the thermal conductivity of nano particles of different shapes will be determined in different directions. Special theoretical corrections must be introduced and taken into account in building the model of the nanotubes with the liquid inside them. The introduced corrections will take into account the fact that the substitution of air by liquid will decrease the thermal conductivity (Kn number) behavior of the nanotubes interior.