Crystal growth of ethanol water solution [for thermal energy storage]

In this study, the authors investigated the mechanism of mushy crystal formation and the state of a mushy layer formed on a cooling surface, with the objective of utilizing the ethanol water solution as a coolant or a thermal energy storage material. To do this, the effect of surface temperature on crystal growth of ethanol water solution was investigated for various concentrations of the solution. Two types of experiments were carried out in the present work in order to study the mechanisms of crystal formation and growth. In one experiment, the authors studied the mechanism of crystal formation within a minute droplet of ethanol water solution, and in the other, the mechanism of the crystal growth in the mushy layer formed in a liquid pool in contact with a cooling surface. For the observation of crystal formation and growth, they used a high-speed photographic system, a CCD camera and a microscopic photographic apparatus.