Numerical Simulation and Experimental Investigation on Thermal Bridge Effect of Vacuum Insulation Panel with Cavities
Abstract
As a super insulation material, Vacuum insulation panel (VIP) integrates high efficiency, energy saving and environmental protection. Its thermal conductivity is 1/5 - 1/10 of the traditional thermal insulation materials and used in some fields. However, due to the thermal conductivity of the outer barrier film and the inner core material are quite different, uneven thermal transfer causes vital thermal bridge effect. Thermal bridge effect has been the focus of VIP research. In this paper, the thermal bridge effect on the edge of VIP with and without cavity is studied by the method of numerical analysis and experimental investigation. This work defined the edge of the linear thermal transmittance rate and point thermal transmittance rate and effective thermal conductivity as evaluation index. Three kinds of VIPs with different cavity shapes were set up and the thermal bridge effect was analyzed. The edge linear and point thermal transmittance rate of the VIP with cavity is higher than without cavity, and cavity will increase the thermal bridge effect of VIP. Different cavity shapes of VIP the evidence difference existed in the thermal bridge effect; VIPs with circular cavity have minimum thermal bridge. Choosing a continuous smooth cavity shape is beneficial to reduce the thermal bridge effect.
