Ba(OH)2·8H2O 作为一种中低温区间理想的相变材料,具有高潜热、性能稳定的优点,但成核过程中过冷严重.本文基于科学法和爱迪生法,用 3 种钡盐和 3 种常用成核剂进行了实验,结果表明,质量分数 4%的Ba(OH)2·H2O效果最好,可以将过冷减小至1℃以内,其他成核剂减小过冷度效果不稳定或者会增大过冷度.4%Ba(OH)2·H2O成核剂的加入对基材Ba(OH)2·8H2O的储热性能影响不大,通过DSC测试,潜热为267.7kJ/kg,相变温度为77.9℃.通过100次循环实验,4%Ba(OH)2·H2O+96%Ba(OH)2·8H2O复合相变材料的相变温度和相变潜热变化很小,最大影响幅度分别为0.63%和3.81%,热物性较为稳定.因此,4%Ba(OH)2·H2O可以作为Ba(OH)2·8H2O理想的成核剂在工业中应用.%Barium hydroxide octahydrate, as a phase change material used in medium-low temperature, is widely used in industries due to its high stability and high latent heat. However, there's serious supercooling during its phase change process. Based on the scientific method and Edison method, experiments for two frequently used kinds of nucleating agents including barium salt and three others were conducted. The addition of 4% of Ba(OH)2·H2O as the nucleating agent showed the best supercooling degree of ＜1℃ with little influence on thermal properties of main material, while other nucleating agents either were not stable or increased the degree of supercooling. The latent heat and the phase change temperature are 267.7kJ/kg and 77.9℃ respectively as determined from the DSC test. After 100 times cyclic experiments, the phase change temperature and phase change latent heat of the composite PCM approximately remained constant, only changed 0.63% and 3.81% respectively, indicating the thermal physical properties are stable. Therefore, 4% Ba(OH)2·H2O can be considered as an ideal nucleating agent to be applied in industry.
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