气凝胶及其复合绝热材料的导热系数测量  

Thermal Conductivity Measurement on Silica Aerogel and it's Composite Insulation Materials

作　　者：魏高升[1] 刘育松[2] 张欣欣[3] 刘登瀛[4] 

机构地区：[1]华北电力大学电站设备状态监测与控制教育部重点实验室,北京102206 [2]北京市可持续发展中心能源部,北京100083 [3]北京科技大学机械工程学院,北京100083 [4]中国科学院工程热物理研究所,北京100190

出　　处：《工程热物理学报》2011年第4期667-670,共4页Journal of Engineering Thermophysics

基　　金：国家自然科学基金(No.50806021);中央高校基本科研业务费专项资金(No.10MG22)

摘　　要：摘要采用瞬态热带法在不同压力和不同温度下对气凝胶、硬硅钙石-气凝胶及陶瓷纤维-气凝胶复合绝热材料的导热系数进行了测量。结果表明,随着测试压力的降低,三种材料的导热系数都显著降低,在大约10~4Pa时基本趋于常数;随着温度的升高,三种绝热材料的导热系数几乎与温度的立方成正比;当气凝胶的密度为145kg/m^3时,其导热系数具有最小值,而气凝胶密度对复合型绝热材料导热系数的影响不大。误差分析表明室温环境下的测量误差在3%以内。The transient hot-strip（THS） method was used to measure the thermal conductivity of silica aerogel,xonotlite-aerogel and ceramic fibre-aerogel composite insulation materials in different pressures and temperatures.The measurement results show that the thermal conductivity of all of the measured materials decreases significantly with the drop of pressure,and reaches to a constant at about 10~4 Pa.The thermal conductivity of all of the measured materials increases cubic with the rise of temperature.The thermal conductivity of silica aerogel has a minimum value when the density is about 145 kg/m^3.The density of silica aerogel has little influence on thermal conductivity of the composite insulation materials.The thermal conductivity measurement uncertainty is estimated less than 3 percent at ambient temperature.

关 键 词：热物性 导热系数 瞬态热带法 气凝胶 纳米孔绝热材料 

分 类 号：TK124[动力工程及工程热物理—工程热物理]