间隔层纤维纸微观结构及热物理性质研究

Study on the Microstructures and Thermophysical Properties of the Spacer Fibre Papers

关键词:  多层绝热  间隔层纤维纸  压汞法  瞬态平面热源法

Key Words:multilayer insulation  spacer fibre papers  mercury intrusion porosimetry  transient plane source method

摘要:纤维纸因其材料轻质、厚度较小及低导热系数等优点，适用作多层绝热间隔层。本研究采用扫描电子显微镜、压汞法和瞬态平面热源法，探究了玻璃纤维纸、植物纤维纸和化学纤维纸的微观结构及热物理性能。结果表明，玻璃纤维和化学纤维表面光滑，横截面呈圆形状；植物纤维具有天然纹理，横截面为扁平状。各纤维纸的纤维直径存在显著差异，且玻璃纤维纸的纤维直径最小。3种纤维纸中，化学纤维纸的孔隙率最小（83.62%），植物纤维纸则拥有最大的总孔隙体积（7.174×10^-3 m³/kg），而玻璃纤维纸具有最大的总孔隙面积（3 889 m²/kg）。在热物理性质方面，玻璃纤维纸的水平、垂向导热系数及比热容均最低，但热扩散系数则显著高于植物纤维纸和化学纤维纸。

Abstract:Fibre papers are appropriate for utilisation as multilayer insulation spacers due to their lightweight， thin， and low thermal conductivity properties. The microstructures and thermophysical properties of glass-fibre paper， plant-fibre paper， and chemical-fibre paper were investigated experimentally using scanning electron microscopy， mercury intrusion porosimetry， and transient plane source methods. The results showed that the glass fibres and chemical fibres exhibited smooth surfaces and rounded cross-sections， whereas the plant fibres displayed natural textures and flat cross-sections. Significant differences in fibre diameter were observed among the various types of fibre papers， with the glass-fibre paper possessing the smallest fibre diameters. Among of the three kinds of fibre papers， chemical-fibre paper exhibited the lowest porosity （83.62%）， plant-fibre paper demonstrateed the greatest total pore volume （7.174×10^-3 m³/kg）， and glass-fibre paper showed the largest total pore area （3 889 m²/kg）. In terms of thermophysical properties， glass-fibre paper exhibited the lowest horizontal and vertical thermal conductivities， as well as specific heat capacity. However， the thermal diffusivity of glass-fiber paper was significantly higher than that of plant-fibre paper and chemical-fibre paper.