石蜡和石墨复合相变材料的导热性能研究

石蜡作为相变材料的不足之处在于石蜡的导热系数低.为了改善石蜡的导热系数,实验利用导热系数较大的石墨和具有较高储热能力的石蜡制备出复合相变储能材料,分析了储热、放热过程中,石墨对石蜡传热特性及相变的影响.结果表明:石墨的掺入增加了复合材料的导热速率,减小了传热的波动性;复合材料的相变时间明显提前,固液相界面的移动加快,相变时间范围明显缩短,而相变温度区间基本不变.

STUDY ON THERMAL PROPERTIES OF COMPOSITE PHASE TRANSITION MATERIALS OF PARAFFIN/GRAPHITE

An inadequacy of paraffin, as phase transition material, is its low thermal conductivity. In order to improve the thermal conductivity of paraffin, in this experiment, the composite phase transition material was prepared using graphite with high thermal conductivity and paraffin with larger heat capacity. Its characteristic of heat transfer in the heat storage and release process is analyzed, and the affection of graphite to the heat transfer rate and phase transformation of paraffin is also studied. The results show that the admixture of graphite in the paraffin could increase thermal conductivity, reduce the fluctuation of heat transfer, with phase change time advanced obviously and phase transition time-frame shortened clearly, while little effect on phase transition temperature range is observed.