Multi-vapor embryos nucleation process and spinodal analyses of expandable superheated water system

A homogeneous nucleation process in superheated water is studied with molecular dynamics simulation. System temperature and pressure are controlled with Langevin dynamics and the volume is variable. During the simulation, there can be seen many regions with no molecules, which are termed vapor embryos here. The vapor embryo nucleation and phase transition process of the system is studied phenomenologically. Vapor embryos violate some predictions of classical bubble dynamics theory, which indicate that it is different from bubble. Systems under different temperature are simulated to investigate the effects of superheated rate. The spinodal limit of superheated water at atmospheric pressure is determined at about 535 K.