Nanofluids are binary mixtures of nanosized solid particles (<100nm) and liquids with volumetric concentrations usually less than 5% that have exhibited enhanced thermalcharacteristics. The underlying heat transfer mechanisms of their behaviour are unconfirmed. The overall impact of global domain-wide thermophoretic effects in nanofluids for different nanoparticle sizes is believed to be one of the driving mechanisms
giving rise to the observed phenomena. Thermophoresis is analysed with the use of a custom-made molecular dynamics simulation code that models the kinematic behaviour of a simplified nanofluid in a domain with a temperature gradient. Despite nanoparticles found to be significantly more mobile than fluid molecules, no net migration effects of
nanoparticles are discovered across the temperature gradient of the system for all nanoparticle sizes tested throughout the simulation. It has been concluded that even though local stochastic nanoparticle-level thermophoretic effects are important, global domain-wide directional thermophoretic forces have not been observed under these circumstances.