Abstract
Behaviors of the vapor bubbles generated by the liquid-liquid direct-contact evaporation were investigated experimentally. Heat was supplied to the top surface of a per-fluorocarbon PF5050 liquid pool by the impingement of the downward hot water jet. Because water and PF5050 were immiscible with each other, a continuous (non-dispersed) horizontal liquid-liquid interface appeared. In addition, there were a large number of liquid droplets of PF5050 floating on the interface in case of the large water flow rate. The generated vapor bubbles broke up the thin PF5050 liquid film above them and then separated from the liquid-liquid interface. The sizes of the bubbles wee measured at the moment just after they were released into the water pool. The value of the buoyancy force acting on the unit area of the thin liquid film was important to make clear the mechanism of the liquid film breakdown phenomenon.
