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Evaporation driven by conductive heat transport

Homes, Simon; Heinen, Matthias; Vrabec, Jadran; Fischer, Johann

FG Thermodynamik und Thermische Verfahrenstechnik

Molecular dynamics simulations are conducted to investigate the evaporation of the truncated (2.5σ) and shifted Lennard–Jones fluid into vacuum. Evaporation is maintained under stationary conditions, while the bulk liquid temperature and the thermal driving force gradient are varied over wide ranges. It is found that the particle flux and the energy flux solely depend on the interface temperature. Both of these quantities are correlated to estimate their values for macroscopically large systems. The latter is analysed by a hydrodynamic energy balance, considering conductive heat transport by Fourier's law. Following the Hertz–Knudsen approach, the evaporation coefficient is determined and found to be in good agreement with literature data based on the kinetic equation for fluids and molecular dynamics.