過冷却水の凝固に及ぼす伝熱面性状の定量的評価 Evaluation of Characteristics of Surface which Influence the Initiation of Freezing of Supercooled Water
It is essential to clarify the supercooling phenomenon, as it is one of the important problem for carrying out the ice storage system, effectively. In this report, the effect of the characteristics of the surface as a heterogeneous nucleation of water was investigated. Experiments on freezing of supercooled water were carried out using various kinds of heat transfer surfaces. The type of the surface used in the experiments were, electrolyticaly polished copper surface, buffed copper surface, gold-plated surface, nickel-plated, porous copper surface, silicone surface, Teflon surface and acrylic surface. The results indicate that the probability of freezing is highly dependent upon the characteristics of the surface. However, by considering the characteristics of the surface as a density of the spots having a high ability of nucleation, it was found that the distribution of the probability of freezing for each surface can be expressed using a parameter τ. A physical meaning of the parameter τ was discussed and suggested as a function of the surface energy and the surface roughness.
日本冷凍空調学会論文集 14(3), 293-301, 1997-11-01