【摘要】 开孔聚氨酯是真空绝热板普遍采用的一种芯层材料。本文建立了开孔聚氨酯泡沫多孔介质材料的简化单元体模型,描述其微尺度空间结构,并导出了气相和固相热传导计算公式、热辐射等效导热系数计算公式、材料总有效导热系数计算公式。计算可得开孔聚氨酯泡沫的导热系数与固体基质导热系数、厚度、泡孔内稀薄气体气压值等因素有关。实验测量了开孔聚氨酯泡沫真空绝热板的导热系数,模型计算值与实验测量值比较具有良好的一致性,文章对保温绝热材料的研制和绝热性能的提高具有实用价值。更多还原

【Abstract】 The open-cell polyurethane foam is a widely used core material for vacuum insulated panels(VIPs). By establishing the simplified model of open-cell polyurethane foam, the geometric structure inside the foam was illustrated and the mathematic formulas for the equivalent thermal conductivity combined with gas phase and solid phase, for heat radiation equivalent thermal conductivity and for the total thermal conductivity. The calculation results showed that thermal conductivity of open-cell polyurethane foam was related to the thermal conductivity of core material, thickness, and the pressure in VIPs. The calculated results had good agreement with the experimental data. The research result is of great use for the thermal insulation material development and the adiabatic performance improvement.更多还原