共晶盐相变蓄冷材料的热分析动力学研究

Study on Thermal Analysis Kinetic of Eutectic Salt Phase Change Materials for Cool Storage

采用微量量热法对以Na_2SO_4·10H_2O为主体的共晶盐蓄冷材料进行了热分析,测得了材料4.5℃、5.5℃、6.5℃和7.5℃时的等温微量量热数据,以Avrami方程作数据处理的结果表明,该方程可以良好地描述该体系的结晶过程,结晶过程的活化能为157.8 kJ/mol,数值为2.39～2.43的Avrami方程时间指数表明该体系的结晶过程应为三维成核机理。

study of the thermal analysis kinetics of a eutectic salt phase change materials with main component Na2SO4 · 10H2O is presented. The Avrami equation is used to analyze the isothermal DSC data measured under 4. 5℃, 5. 5℃, 6.5℃ and 7. 5℃ by Calvet micro-calorimeter. The analysis indicates that the equation is appropriate for describing the crystallization mechanism. As a calculated result, the activation energy of crystallization is about 157. 8 kJ/mol; raoL Because the time exponents are about 2. 39 to 2. 43, it approves the three-dimensional crystallization mechanism.