Category: Transient Plane Source
Author(s): Hu Zhang, Ming-Jia Li, Wei Gu, Wen-Quan Tao, Wen-Zhen Fang, Zeng-Yao Li
Keywords: Adsorption saturation capacity, Aerogels, Amorphous, Cell structure, composites, environmental, Exothermic, Humidity, Pore Size, porosity, Scanning Electron Microscopy (SEM), Silica nanoporous materials, Temperature, Thermal Conductivity, thermal insulation, Thermal Resistance, Water vapor adsorption capacity
Abstract: Aerogels have a wide range of properties that make them effective thermal insulators. However, these properties are lost when the materials absorb too much water. The goal of this experiment was to determine how temperature and humidity affect the insulative properties of silica nano-porous aerogels. A thermal constants analyzer measured the thermal conductivity of moist silica nano-porous materials using the transient plane source (TPS) method. Results showed that the thermal conductivity of the aerogels increased with humidity which deteriorated the thermally insulative properties. Water is 25 times more conductive than air, so when air in the porous aerogels is replaced by water under high temperatures, the thermal conductivity of the materials increases drastically.
Reference: Journal of Nanoscience and Nanotechnology, 14 (2014) 1-7