泡沫石墨/石蜡复合相变材料热物性研究  

Thermal Characterization of Graphite Foam/Paraffin Composite Phase Change Material

作　　者：肖鑫[1] 张鹏[1] 

机构地区：[1]上海交通大学制冷与低温工程研究所,上海200240

出　　处：《工程热物理学报》2013年第3期530-533,共4页Journal of Engineering Thermophysics

基　　金：国家自然科学基金-云南联合基金重点项目(No.U1137605);科技部国际科技合作项目(No.2013DFG60080);上海交通大学研究生创新基金(No.Z-020-026)

摘　　要：本文采用真空注入法制备了泡沫石墨/石蜡复合相变材料,并比较了其和非真空法制备材料的注入比差异。对制成的复合相变材料进行了结构和热物性的表征及测试。采用激光热导热仪测量了有效热导率,并通过理论模型进行验证。由差示扫描量热仪(DSC)得到了复合相变材料的相变特性。结果表明,真空注入法是制备多孔基材复合相变材料的有效方法,真空法得到的复合相变材料的有效热导率较纯石蜡提高了近311倍。复合相变材料的固-液相变点较纯石蜡无显著变化,受泡沫石墨中石墨骨架高热导率和多孔介质内部热非平衡的影响,复合相变材料的固-固相变点变得不明显。复合相变材料的吸热系数较纯石蜡有很大的提高。Graphite foam/paraffin composite was prepared with vacuum assistance in the present study. The impregnation ratio was studied comparatively under the impregnation with and without vacuum assistance. The structure and thermo-physical properties of the composite phase change material （PCM） were characterized. The thermal conduetivities of the composites were measured by laser flash technique, and the results were compared with the theoretical model. The phase change behaviors of the composites were investigated by a differential scanning calorimetry （DSC）. The results showed that the impregnation process with vacuum assistance was superior to that without vacuum assistance. The thermal conductivity of the composite PCM with vacuum assistance was 311-time higher than that of pure paraffin. The solid-liquid phase change temperature of the composite PCM showed no significant shift, compared with that of pure paraffin, but the solid-solid phase change temperature of composite PCM became unapparent, which was due to the effect of the high thermal conductivity of graphite foam skeleton and thermal non-equilibrium of porous materials. The thermal effusivity of the composite PCM was much larger than that of the pure paraffin.

关 键 词：泡沫石墨 复合相变材料 强化换热 

分 类 号：TK02[动力工程及工程热物理]