This paper is second report that aims at developing the translucent vacuum insulation panels (TVIPs) to contribute retrofitting insulation for existing buildings. In this paper, the authors firstly introduced the simultaneous evacuating and thermal conductivity measurement experiment to evaluate the thermal conductivities of TVIPs and the 3D numerical calculation to predict the thermal conductivities of TVIPs. The thermal conductivities of TVIPs were evaluated by these two method and they were 0.015~0.03 W/(m・K) for spacer core material, 0.007~0.01 W/(m・K) for mesh core material, 0.007~0.008 W/(m・K) for frame core material, respectively. The thermal conductivity of 0.007 W/(m・K) was set as the target value and the VIPs were test produced using different manufacturing processes and the thermal conductivities were measured. A value of 0.011 W/(m・K), which was the closest to the target value, was obtained by enclosing a getter agent in the gas barrier envelope.
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