新型相变蓄热材料的热物性测试

Testing for thermal properties of new phase-change thermal storage material

为了寻找新型相变蓄热材料,对不同配比下NaCl/KCl/MgCl2三元体系的熔点进行了测量,提出了一种新型三元相变蓄热材料质量分数之比为20%NaCl/20%KCl/60%MgCl2;搭建了准稳态法测试试验台,并利用试验台对新型三元相变蓄热材料的主要热物性参数,包括比热、导热系数和熔解热进行了测试。测定温度范围61.21—573.65℃;利用多项式函数对导热系数和比热试验数据进行了拟合,拟合平均相对偏差小于1.5%。试验结果表明,新型相变蓄热材料潜热大、蓄热密度高、且具有较高的导热系数,具有广阔的工程应用前景。

In order to look for the new phase-change thermal storage material, the melting points of different NaCl/ KCl/MgCl2 ternary systems were determined, and a new phase-change thermal storage material of 20% NaCl/20% KC1/60% MgC12 （mass fraction） was proposed. The apparatus of quasi-steady state technique was developed, which was used to measure the specific heat, thermal conductivity and latent heat of the new phase-change thermal storage material in the temperature range of 61.21-573.65℃. The experimental data of specific heat and thermal conductivity were fitted as polynomial functions and the average deviation was less than 1.5%. The result shows that the new phase-change thermal storage material is featured by high latent heat, high storage density and higher conductivity, which can be widely used in the engineering application.