Performance of aerogel composite and foam insulations

Apparent thermal conductivity;thermal insulation;aerogel composite;foam insulation

Alvey, Jedediah ; Brewster ; M. Quinn

关键词: Apparent thermal conductivity;    thermal insulation;    aerogel composite;    foam insulation;   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/49395/Jedediah_Alvey.pdf?sequence=1&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

Building insulation materials have been subjected to various temperature and humidity conditions and their thermal performance during several weeks of controlled environmental exposure has been observed. Several commercially available insulating materials (three aerogel composite blankets, two extruded poly- styrene foams (XPS) and one blown polyurethane foam (PUR) on plywood ) were evaluated. Thermal conductivity (reciprocal of resistivity) was measured with a heat flow metering apparatus at one week in- tervals for five weeks. Insulations were exposed to conditions of 65.6◦C and 90% RH, 65.6◦C and 60% RH, 65.6◦C and 30% RH, and 32.2◦C and 90% RH. Results indicate that humidity levels play a significant role in the performance of PUR on plywood, leading to loss in thermal resistivity up to about 10%. But humidity did not play a significant role in XPS performance, which increased slightly in resistivity during tests. The three aerogel composites were observed to have various levels of degradation of thermal properties, losing about 5% of resistivity during the most extreme environmental conditions. Degradation in the aerogel com- posites was found to be caused by one or multiple of the following: infusion of humid air into the aerogel, sorption of moisture by fibers, chemical degradation of fibers and geometric distortion of the composite.