Abstract: Experiment on different depth of water tank supercooling degree was carried out. The results show that the supercooling degree of the upper water in ice storage tank is higher. In order to reduce the supercooling degree of the water and energy consumption of the chiller, different nucleation additives are tested and it is found that adding nano-copper oxide can reduce the supercooling degree and improve the ice storage efficiency. Appropriate mass fraction of copper oxide nanoparticles is obtained under a certain quality dispersant. When the ice-making temperature is -5℃, 0.10% mass fraction copper oxide suspension is at the top. Supercooling degree of water is also associated with the temperature difference of heat transfer medium. The higher the difference in temperature is, the smaller the supercooling degree.

Key words: ice thermal storage, supercooling degree, nucleation, nanomaterials, phase change

摘要： 在对内融冰式蓄冰槽内不同水层的水进行过冷度测试中发现上层水的过冷度较大.为了降低水的过冷度和冷水机组能耗,通过实验的方法对不同的成核添加剂进行筛选测试,结果显示纳米氧化铜不但在降低过冷度方面效果显著,而且提高了蓄冰效率.最后获取了一定质量分散剂下最佳纳米氧化铜的质量分数,即在-5℃的制冰温度下,质量分数为0.10%的氧化铜悬浊液为最佳配比.在实验过程中发现水的过冷度还与换热介质的传热温差有关,温差越大过冷度越小.

关键词: 冰蓄冷, 过冷度, 成核, 纳米材料, 相变