Molecular Dynamics Simulation on Rapid Boiling of Thin Water Films on Cone-Shaped Nanostructure Surfaces

Abstract

Molecular dynamics simulations (MDS) are employed to investigate the effects of the size of a nanocone on rapid boiling of an ultrathin liquid water film that is suddenly heated by a hot aluminum plate. A physically sound thermostat is applied to control the temperature of the aluminum plate and then to heat the water molecules that are placed on the solid surface. The results show that the cone nanostructures drastically enhance heat transfer from the solid aluminum plate to liquid water and the phase change process from liquid water to vapor. They also have significant effects on temperature histories and the density distributions in the system. In all cases studied, the water molecules above the solid surface rapidly boil after contact with an extremely hot aluminum plate and consequently a cluster of liquid water is observed to move upward during the phase change. It is also observed that the separation temperature associated with separation of liquid water film from the solid surface and its final temperature when the system is at equilibrium strongly depend on the height of the nanocone. Furthermore, in all cases, at a specific time after beginning of boiling, a nonvaporized water molecular layer is formed above the surface of the aluminum plate.

The effect of surface wettability on water vapor condensation in nanoscale

“…The inside four layers of atoms as Pt-like solid wall are built to exchange energy between the water and the heating source or cooling source. Such a setting was adopted to build the heating or cooling surface in previous studies 23 24 25 and has been proved to effectively avoid artificial thermal resistance caused by the applied thermostat 26 . In all cases, we just change the interaction parameters between the cold wall and the water to simulate condensation surface with different surface wettability.…”

Influence of interface wettability on normal and explosive boiling of ultra‐thin liquid films on a heated substrate in nanoscale: a molecular dynamics study

“…Except the references above, Shepherd et al [16] studied the superheat limit on explosive boiling, Esmaeeli et al [17] investigated the explosive boiling in microgravity, and Frost et al [18] studied the effects of ambient pressure on explosive boiling. Literatures [19][20][21][22] investigated the effects of nanostructured solid surface on evaporation and boiling of liquid. Jontz et al [23] studied the effect of surface tension on boiling.…”

Deciphering The Molecular Mechanism Of Water Boiling At Heterogeneous Interfaces

“…The studies of heterogeneous nucleate boiling 34 are limited to the method using such an external biasing eld. More speci cally, the nucleate boiling dynamics have been analyzed by creating arti cial voids in the bulk 35 , introducing negative pressure 36 , superheat the solid surface 37,38 and trap gas in pits and scratches on the surface 39 . While the applied external bias helps to cross-reaction activation barrier, the effect of such arti cial bias needs to be quanti ed 28 .…”