Mechanics of Cooling Liquids by Forced Evaporation in Bubbles

The injection of a nondissolvable gas into a saturated liquid results in subcooling of the liquid due to forced evaporation into the bubble. Previous studies have assumed the rate of evaporation of liquid into the bubble to be independent of the degree of subcooling. In our study, we quantify the bubble growth by direct observation using high-speed imaging and prove that this hypothesis is not true. A phenomenological model of the bubble growth as a function of the degree of subcooling is developed and we find excellent agreement between the measurements and theory. This bubble-cooling process is employed in cooling a liquid. By identification of all heat flows, we can describe the cool-down curve well using bubble cooling, which provides an alternative cooling method for liquids without the use of complicated techniques.