Molecular dynamic simulation of the effect of nanocoating on two-phase evaporative heat and mass transfer

Two-phase cooling such as thin film evaporation is becoming increasingly popular for thermal management of high powered electronics due to the high latent heat associated with the phase change process. Nanoengineered surfaces have been shown to improve two-phase heat transfer performance through enhanced wettability and reduced interfacial thermal resistance. However, how interfacial resistance varies with surface wettability and how such resistance can affect thin-film evaporative transport is still not well understood. In this study, we investigate the evaporative transport characteristics and wetting state of an evaporating thin liquid film on both smooth and nanocoated surfaces using Molecular Dynamics (MD) simulations. The surface wettability between liquid argon and silicon (100) surface coated with 0, 1, and 3 layers of graphene is characterized using equilibrium molecular dynamics methods. The associated interfacial thermal resistances and the evaporation rates are explored using non-equilibrium molecular dynamics methods, in which a hot and cold solid substrate are implemented to facilitate the evaporation and condensation of liquid argon molecules.