Nanoscale liquid-vapor phase-change physics in nonevaporating region at the three-phase contact line

Nanoscale liquid film evaporation is usually associated with super-high heat transport rates and can be found in natural processes and in many industrial and advanced technologies. In this paper, thin film evaporation is simulated in a nanochannel using molecular dynamics to study the effect of varying nanochannel height and film thickness. Three nanochannel heights (16.32, 25.5, and 35.7 nm; constant liquid film thickness=3 nm) and three liquid film thicknesses (2, 4, and 6 nm; constant nanochannel height=25.5 nm) are simulated to study six cases. A nonevaporating film is obtained for all six cases. Hamaker constant, vapor pressure, film thickness, and net evaporation and heat fluxes are evaluated. An additional simulation (case 7) is run with simultaneous evaporation-condensation; no nonevaporating film is obtained. Thus, the creation of a nonevaporating film, and its thickness (if the film forms), depends on the combination of three factors, namely, vapor pressure, substrate temperature, and solid-liquid molecular interaction strength.