  The turbulent flow of a fluid carrying trace amounts of a condensable species
through a differentially cooled vertical channel geometry is simulated using
single-phase direct numerical simulations. The release of latent heat during
condensation is modeled by interdependent temperature and vapor concentration
source terms governing the relation between the removal of excess vapor from
the system and the associated local increase in fluid temperature. A coupling
between condensation and turbulence is implemented via solutal and thermal
buoyancy. When compared to simulations of an identical system without phase
transition modeling, the modifications of the subcooled boundary layer due to
the transient and highly localized release of latent heat could be observed. A
separate analysis of fluid before and after phase transition events shows a
clear increase in post-interaction streak spacing, with the release of latent
heat during condensation events opposing the cooling effect of the channel wall
and the associated damping of turbulence.
