Effect of Large Pores in Silica Aerogels on the Gaseous Thermal Conductivity of Vacuum Insulation Panels
The pore structure of core material has a significant effect on the thermal insulation properties of vacuum insulation panels (VIPs).Silica aerogels are the most promising core material due to their very small pores less than 100 nm.However,this material also consists of many pores larger than 100 nm,and these large pores certainly affect the thermal insulation performance of VIPs.The information on pores less than 100nm of a silica aerogel with a density of 0.15g/cm3 was derived from nitrogen sorption,and then the effects of size and percentage of large pores in this silica aerogel on the gaseous thermal conductivity and tolerable internal gas pressure of VIPs were quantitatively described by using Kaganer model.The results indicated that the volume of large pores occupied 58% in the total pore volume of the prepared silica aerogel.With decreasing size or percentage of large pores in silica aerogel,the gaseous thermal conductivity of VIPs decreases while the tolerable internal gas pressure increases.Moreover,there is a linear relationship between the tolerable internal gas pressure and the size of large pores in log-log coordinate.
vacuum insulation panels silica aerogels large pore gaseous thermal conductivity
Yang Hailong Hu Zijun Li Junning Sun Chencheng Wu Wenjun
Aerospace Research Institute of Materials & Processing Technology, Beijing, 100076, P.R.China
国际会议
The 12th International Vacuum Insulation Symposium (IVIS 2015)(第十二届国际真空绝热材料会议)
南京
英文
40-44
2015-09-01（万方平台首次上网日期，不代表论文的发表时间）