Due to different structures, the heat transfer mechanisms of vacuum glass and insulating glass are also different. Figure 2 is a simplified heat transfer diagram. The heat transfer in the center of the vacuum glass consists of radiation heat transfer and support heat transfer, in which residual gas heat transfer is ignored. Insulating glass is composed of gas heat transfer (including conduction and convection) and radiation heat transfer.
It can be seen that in order to reduce the heat transfer caused by temperature difference, both vacuum glass and insulating glass must reduce radiative heat transfer. The effective method is to use glass coated with low-emissivity film (LOW-E Glass), taking into account other optical performance requirements, the lower its emissivity (also called emissivity), the better. The difference between the two is that vacuum glass also needs to reduce the heat transfer of the lattice supports as much as possible. According to its own patent, Xinliji Company uses an open ring-shaped (or C-shaped) support with a diameter of 0.5mm, and the lattice spacing is 25mm. , its thermal conductivity is about 0.5Wm-2k-1. Insulating glass should reduce gas heat transfer as much as possible. In order to reduce gas heat transfer and take into account factors such as sound insulation and thickness, the air layer thickness of insulating glass is generally 9-24mm, mostly 12mm. To reduce gas heat transfer, gases with large molecular weights (such as inert gases: argon, krypton, xenon) can be used to replace air, but even so, gas heat transfer still dominates. ?