Abstract
Understanding the effects of microstructural parameters on the heat transfer through an aerogel-based vacuum insulation panel (VIP) is important for the design and development of thermal insulation materials. The present work first prepared the aerogel-based VIP and characterize its microstructure through scanning electron microscopy and nitrogen gas adsorption analysis. A theoretical model for the thermal conductivity of the aerogel-based VIP was then presented and validated with experimental results. Based on the model, the effects of microstructural parameters, i.e. particle diameter and pore diameter, on the thermal conductivity of the aerogel-based VIP were explored. The results indicated an extremely low thermal conductivity with approximately 1.7 × 10−3 W·m−1·K−1 can be achieved as the particle diameter and pore diameter are 1 and 10–15 nm, respectively. Furthermore, the microstructure effect under various service time of the aerogel-based VIP was considered for practical heat transfer engineering. It was found that the increase rate of the thermal conductivity decreases with a decreased particle diameter or an increased pore diameter. The microstructure effect modeling of the aerogel-based VIP could be of great advantage to heat transfer engineering applications aiming to reducing heat loss and saving energy.
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Yuying Liang
Yuying Liang is an M.S. student at Guangzhou University, China, under the supervision of Prof. Huijun Wu. She obtained her B.E. degree in heating, ventilating and air conditioning at Guangzhou University, China, in 2015. Her research mainly focuses on thermal performance and service life of building thermal insulations for energy saving. She has published 10 papers in refereed journals.
Yunfei Ding
Yunfei Ding is a professor of building services engineering at Guangzhou University, China. He received his B.E. degree at Harbin Institute of Architectural Engineering in 1990 and his Ph.D. from South China University of Technology in 2004. He is director of the center of building environment and energy efficiency, Guangzhou University, China. His research interests include heat and mass transfer, phase change material, HVAC, and building energy efficiency. He has published more than 50 papers in refereed journals and conference proceedings. He is currently working on optimization and control of air conditioning system and building energy efficiency.
Yanchen Liu
Yanchen Liu is a Ph.D. at Department of Building Science, Tsinghua University. During her graduate studies, she has been mainly engaged in post occupant evaluation of green building technology and operational performance, and participated in four national key research projects. In view of the performance gap widely existing in the actual operation of buildings, she conducted the monitoring and analysis of building energy efficiency and IEQ, the integration of monitoring and modeling work on energy use, IEQ and comfort, as well as policy research through System Dynamic Modelling approach. She has published 5 SCI papers and 8 international conference papers.
Jianming Yang
Jianming Yang is a Ph.D. candidate in Guangzhou University. He obtained his B.E. degree in heating, ventilating and air conditioning at East China of Jiaotong University in 2013 and his M.S. degree in Guangzhou University in June 2016, under the supervision of Prof. Huijun Wu. His research mainly focuses on modeling and optimizing heat transfer of novelty thermal insulations. He has published 25 papers in refereed journals, including 5 SCI papers.
Hua Zhang
Hua Zhang is a Ph.D. candidate in Jilin University. He obtained his M.S. degree in chemistry at East China University of Technology in June 2016, under the supervision of Prof. Huanwen Chen. His research mainly focuses on biological mass spectrometry. He has published 23 papers in refereed journals, including 9 SCI papers.