真空绝热板热桥效应传热模型分析与优化

Modeling and Simulation of Thermal Bridge Effect of Vacuum Insulation Panels

对真空绝热板(VIP)热桥效应进行了数值分析,引入了边缘线性传热率的概念作为衡量热桥效应大小的基准量,基于稳态传热边界条件建立热流传递模型,对各影响因素进行分析和计算。研究结果表明,主要影响因素有芯材的导热系数及厚度,隔气结构的导热系数及厚度,VIP间填充介质的导热系数及厚度,VIP的规格。其中,边缘线性传热率随着芯材的导热系数及厚度的增加、隔气结构导热系数及厚度的减小、填充介质的导热系数及厚度的较小、VIP规格的增大呈现减小的趋势。文章结合影响因素,提出减小隔气薄膜的厚度与导热系数,减小芯材与填充介质的导热系数,适当增大VIP的规格,提高安装工艺等优化措施减小热桥效应。

The thermal bridge effect of vacuum insulation panel（VIP）was evaluated in terms of linear thermal transmittance,mathematically modeled as the edge thermal flux under the steady-state heat transfer boundary conditions,and numerically simulated in finite element method（FEM）.The impact of the thermal conductivity,and structures of the VIPs and its components on the linear thermal transmittance was investigated.The simulated results show that the thermal conductivity and thickness of the components,and VIP＇s size all have a major impact on the linear thermal transmittance.For instance,the linear thermal transmittance decreases with the increase of thickness and thermal conductivity of the core material,with the decrease of thickness and thermal conductivity of both the barrier and filler materials,and with an increase of the VIP＇s size.We suggest that the simulated results be of much technological interest.