Preparation and characterization of vacuum insulation panels with super-stratified glass fiber core material

Abstract

VIPs (vacuum insulation panels) with super-stratified glass fiber core material were prepared by CSB (centrifugal-spinneret-blow) process. The fiber orientation of the super-stratified glass fiber core material was concentrated in the X–Z plane which was perpendicular to the heat transfer direction. The initial thermal conductivity of this novel VIPs was only 1.25mW/(m K) which performs up to two times more thermal insulation than conventional wet core material (2.62mW/(m K)). The thermal conductivity of VIP with CSB-3μm was significantly lower than that calculated from the theoretical curves with mean pore size of 10 μm. The results demonstrated that thermal conductivity of VIP with CSB-3μm attained 1.25, 1.76, 2.04, 2.91, 3.45, 4.58, 9.16, 13.03mW/(m K) under the pressure of 0.03, 0.06, 0.09, 0.3, 0.5, 0.9, 5 and 10 mbar, respectively. This is a great breakthrough to dramatically increase the service life-span of VIP with glass fiber core material. Their further advantages compared to conventional wet process are their lower energy consumption and cost.