Research on solidification of electrolyzed water for ice storage system

在动态型冰蓄热系统中，选择水作为蓄热材料是有益的，因为它既环保又便宜。对于动态型冰蓄冷系统，采用的方法有很多。其中一种方法是将冷却管内的水保持在过冷状态，并将其排出管道后将其固化。但是，由于管道内发生过冷水的凝固，存在堵塞问题。在本研究中，选择电解水来寻找控制凝固的可能性。在6.0 ~ 11.0 pH范围内改变氢离子浓度参数，考察了pH值对冷冻过冷程度的影响。结果发现，当pH值从中性点向两侧移动时，冷冻时的过冷程度增加。考虑了pH值对平均团簇大小的影响，讨论了成核的物理机制。由于质子跃迁的发生，pH值从中性偏移，团簇变小。通过汽化实验检验了聚类大小的差异，并证实了这一点。此外，还对电解水的主动冻结控制方法进行了实验研究。结果表明，在电解水上施加电场或超声波是有效的。

In dynamic type of ice thermal storage system, selecting water as a heat storage material is beneficial, because it is environmentally friendly and cheap. There are many methods adopting for dynamic type of ice storage system. Keeping water at supercooling state in a cooling pipe and solidifying the water after discharging it out of the pipe is one of the methods. However, it has a problem of blockade due to solidification of supercooled water taken place inside the pipe, accidentally. In this research, electrolyzed water was selected to find the possibility of controlling the solidification. The parameter for hydrogen ion concentration was varied from 6.0 to 11.0 pH, and the effect of pH on the degree of supercooling at freezing was investigated. It was found that the degree of supercooling at freezing increased by shifting the pH from the neutral point to both sides. The mechanism of nucleation physics was discussed by considering the effect of the difference in pH on the average cluster size. The cluster tends to become smaller by shifting pH from the neutral due to the occurrence of proton jump. The difference in cluster size was examined through vaporizing experiments, and it was confirmed to be true. Furthermore, active freezing control methods on electrolyzed water were also investigated, experimentally. It was found that applying an electric field or ultrasonic waves on electrolyzed water were effective.