Molecular dynamics simulation of characteristics of the nanodroplet evaporation

Abstract

The molecular dynamics method is used to simulate the evaporation process of nanodroplets on heated substrates by LAMMPS software. The simulation process includes three stages: the relaxation of argon droplets at 84K, heating the substrates to 200 K, keeping the substrates temperature at 200 K to observe the evaporation of the droplet. By measuring the change of the whole morphology of the droplets during the evaporation process, the changes of the edge thickness are obtained. By analyzing the atomic velocity and displacement, the trajectories of the particles at the edge of the evaporation process are revealed and distribution of the temperature of the droplets are expressed. It is concluded that when the substrates at 200K, the whole droplet evaporation process is conclude four stages: fixed evaporation stage, the stick slip motion stage, once again into the fixed evaporation stage and fixed contact angle and the contact radius are decreasing the evaporation process until the end. Finally, the experimental platform was set up to verify the validity of the simulation. Without considering the influence of plate roughness, the height variation of the droplet obtained from the experiment has a high consistency with the simulation results.