Review on direct contact condensation of vapor bubbles in a subcooled liquid

Condensation of vapor bubbles in a subcooled liquid is known to influence heat transfer and pressure oscillation in subcooled boiling and direct contact condensation. This study reviews the published literature concerning interfacial heat transfer and bubble dynamics in the process of bubble condensation. The correlations for bubble condensation are analyzed and evaluated with a database covering a wide range of Reynolds, Jacob, and Prandtl numbers. Then, the investigations addressing bubble dynamics are reviewed, which focus on the bubble condensation patterns, motion, collapse, and the pressure oscillations induced by bubble condensation, as well as the effect of noncondensable gas and field. Despite the extensive experiments of bubble condensation available in the literature, it is shown that there is still a shortage of investigation focused on the variation of thermal boundary layer and turbulence formed near the bubble at the micro-scale, which could help to develop the prediction method of bubble condensation in the future. The transportation of noncondensable gas inside the mixture bubble and effect of capillary waves formed on the bubble surface on the actual vapor-liquid contact area and thermal boundary are also suggested to be further investigated to gain the thorough understanding of the bubble condensation process.