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.
出处
《工程热物理学报》
EI
CAS
CSCD
北大核心
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)
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
thermophysical properties
thermal conductivity
transient hot-strip method
aerogel
nano-porous insulation material