Lattice Boltzmann simulation of condensation in the presence of noncondensable gas

In this paper we use the multiphase multispecies Lattice Boltzmann method to investigate the influence of non-condensable gas on condensation. Condensation on a horizontal cold wall as well as that on a vertical wall with droplet movement is investigaged. The presence of non-condensable gas obviously reduces the condensation mass rate as well as the heat flux compared to condensation from pure vapor. The waiting time before nucleation is increased with non-condensable gas, and the wetting characteristics are also changed (the contact angles are increased), which further influences the heat transfer. Correlations of the relationship between droplet diameter and condensing time for different surface wettability, or contact angles, as well as different air mass fraction are obtained. As for condensation on a surface parallel to the gravitational force, it's demonstrated that the presence of non-condensable gas reduces the droplet departure diameter and increases the period between subsequent droplet formation and departure.