A study on the thermal resistance over solid–liquid–vapor interfaces in a finite-space by a molecular dynamics method

Abstract

Molecular dynamics of argon atoms in a nano-triangular channel which consists of (111) platinum walls were studied. The molecular dynamics simulations aim to gain understanding in the heat transfer through the channel including the influence of the contact resistances which become important in small-scale systems. The heat transfer properties of the finite-space system were measured at a quasi-steady non-equilibrium state achieved by imposing a longitudinal temperature gradient to the channel. The results indicate that the total thermal resistance is characterized not only by the thermal boundary resistances of the solid–liquid interfaces but also by the thermal resistance in the interior region of the channel. The overall thermal resistance is determined by the balance of the thermal boundary resistances at the solid–liquid interfaces and the thermal resistance attributed to argon adsorption on the lateral walls. As a consequence, the overall thermal resistance was found to take a minimum value for a certain surface potential energy. A rich solid–liquid interface potential results in a reverse flow along the wall which gives rise to a stationary internal flow circulation. In this regime, the nanoscale-channel functions as a heat-pipe with a real steady state.