Relating to the problem of supercooling for ice storage devices, basic investigation was carried out by performing numerous experiments and statistical analysis. In the experiment, freezing temperature of supercooled water was measured. It was observed that the property of heat-transfer surface and the cooling rate affect the ice appearance process. The freezing temperature seems to be a statistical phenomenon, and the frequency distribution differs from one kind of surface to the other. The type of surface used for the experiment were copper disks, which were electrolytically polished, buffed, gold-plated, nickel-plated and porous. The results indicate that supercooled water can be frozen at higher temperature on coarser surface than on smoother one and at slower cooling rate than faster one. The probability of getting ice within the unit surface area in unit time interval is introduced as a function of surface temperature and surface property including roughness. Finally, the method to predict the most probable freezing temperature of supercooled water for a given cooling condition and surface property is proposed
