Effective thermal conductivity of nanofluid from molecular dynamics simulations

Nanofluids, a working fluid containing nanoparticles, have been used to improve the performance of currently available heat transfer liquids. The purpose of this research is to investigate the enhancement of the Cu-Ar nanofluid thermal conductivity by combining linear response theory with molecular dynamics simulations. The calculated effective thermal conductivity was found to be 8.3% higher than the base fluid's experimental data for a nanoparticle volume concentration of 0.43%, which is much higher than predicted by the Maxwell 3φ theory. The heat flux is decomposed into that in the liquid, the solid, and the interactions between the two parts. This study suggests that collisions are the main cause of the nanofluid thermal conductivity enhancement and the nanoparticle itself plays a minimal role. Adsorption near the nanoparticle was also found in the simulations.