Molecular dynamics simulation on phase transition behaviors of R410A liquid film over solid copper surface

Currently, two-phase transition as a preferred heat transfer mode has gained great attention in thermal engineering. However, the phase transition performance of liquid film is highly affected by the components, and the studies of refrigerant mixtures is still needed to be explored in depth. In this paper, molecular dynamics simulation method is employed to study the vaporization processes of R410A mixture under various temperature conditions. Here, R410A liquid film is first heated by the bottom substrate and then is condensed on the upper part of copper surface. The results reveal that only the evaporation phenomenon takes place on the solid wall with temperature below 300 K, while the bubble nucleus appears as temperature rises to 350 K, leading to heat transfer mode converting into explosive boiling. Meanwhile, the phase transition rate performs a positive exponential relationship in terms of heating temperatures. Furthermore, the density, potential energy, and temperature distributions are also analyzed to interpret the simulation results. These indicate that hightemperature is more favorable for breaking the potential restriction and enhancing the heat transfer of explosive boiling. The finding is also helpful to provide significant insights into the nanoscale phase transition and relevant mechanisms of liquid refrigerant mixtures.