Bubble growth dynamics in a nano-pore via molecular dynamics and phase field simulations*

We use phase-field (PF) and molecular dynamics (MD) to simulate the growth process of a single bubble nucleated in a nano-pore. We compare the growth rate and temperature distribution of PF predictions with those from MD simulations applied to a Lennard-Jones system. The domain is composed of a tethered solid wall, a cavity, and a liquid phase that transitions to vapour when the system temperature exceeds the saturation point. A uniform heating is applied at the bottom of the solid surface. The key physical parameters necessary to close the PF model are obtained by solving the inverse problem using the initial stages of the MD simulations. After this short period, both MD and PF simulations are carried out independently. The results show good agreement between the continuum model and the MD data. Interestingly, the transition between the initial stages of the bubble growth can be captured by the MD-PF model. The proposed methodology paves the way for a multi-scale modelling approach to study boiling from first principles including the highly complex phenomenon of nucleation.