Fundamental Study of the Enhancement of Flash Evaporation in a Steam Accumulator by Means of the Injection of Bubble Nuclei

As an attempt to develop an efficient steam accumulator, an experimental investigation has been made of the effect of injection of bubble nuclei generated by electrolysis on the flash evaporation of warm water exposed to a sudden pressure drop in a container. From the results, it is realized that artificial nucleation enhances the flash evaporation of the pool water, thereby increasing the flash evaporation efficiency in the late evaporation period, especially for the cases of lower liquid temperature, higher liquid level and smaller superheat. Semi-empirical equations are deduced for predicating the practical evaporation efficiency when the mass velocity of vapor declined to any given values, from the dimensionless depth of the superheated zone and the mass velocity of electrolytic gases.