本文介绍了纳米铜-赤藻糖醇的配制方法,通过材料热物性变化的内部机理研究了循环过程中此相变材料(PCM)的衰减过程.根据差示扫描量热仪(DSC)以及导热系数测试仪(Hotdisk)的测试数据,对导热系数、过冷度、相变潜热在100次热循环过程中的0次、20次、40次、60次、80次、100次的变化原因进行了理论分析.采用热力学熵的热力学原理引出物质熵,从物质熵增的角度,总结了相变材料的衰减原因.结果表明:相变材料经过100次循环后,各项性能参数都出现了不同幅度的下降.导热系数随着纳米铜的添加量增加下降幅度减小;赤藻糖醇添加纳米铜后的过冷度整体上小于没有添加的过冷度;随着循环次数的增加,潜热值后期整体下降幅度加大.%This paper briefly introduces the preparation of nanocopper-erythritol. According to the internal mechanism of the change of thermal property in phase change material ( PCM) , the causes of material changes in the circulation process are explored. Using test data from differential scanning calorimetry( DSC) and a thermal conductivity tester ( Hotdisk) , the heat conductivity coefficient, supercooling degree, and latent heat during 0, 20, 40, 60, 80, and 100 thermal cycles are analyzed. The change process of PCMs is summarized based on the point of growth of material entropy which is introduced through the thermodynamic principle of thermody-namic entropy. Experimental results show that after 100 cycles, the performance parameters of the phase change material have been decreased differently. The declining degree of the thermal conductivity coefficient is lower when the amount of nanocopper increases. The overall cooling degree of erythritol with nanocopper added is less than that of erythritol without nanocopper. In the latter stages, the declining degree of the latent heat value increases as the number of cycles increases.
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