Finite -Element Thermal Analysis of Thermal Bridge of Vacuum Insulation Panels Based on Temperature-Dependent Laminate Properties

AbstractVacuum Insulation Panels(VIPs) have been regarded as a super thermal insulating material with high efficiency. In order to enhance the ability of the barrier material, which is used as the envelope in VIPs, to resist the permeation of water vapor and gases through it, aluminum is used in the laminate, thus thermal bridge is triggered due to the much higher thermal conductivity of Al compared with that of the core material. In this study, accounting for the temperature dependent thermal conductivity of different materials in the envelope, thermal flux of each layer was calculated through a two -dimensional nonlinear steady-state heat transfer model by Finite Element Method(FEM). The relationship between thermal flux of each layer in the envelope with different temperature differences between the warm and cold side of the VIP was presented, which could provide theoretical basis to optimize each layer