含水率对建筑外墙保温材料导热性能的影响

Effect of Moisture Content on Thermal Conductivity of Exterior Wall Insulation Materials

关键词:  空心微珠  保温材料  含水率  相对饱和度  导热系数

Key words:  hollow sphere(HS)  thermal insulation material  moisture content  relative saturation  thermal conductivity

摘要:

通过烧结空心微珠（HS）坯体制备A1级高性能空心微珠保温材料（HS板），研究了含水率对HS板、发泡聚苯乙烯板（EPS板）及玻璃纤维棉板（GW板）导热系数的影响，探究了饱和吸水率及密度对HS板导热系数的影响.结果表明：试样的导热系数均随含水率的增大而逐渐变大，当含水率（质量分数）为5%时，EPS板、HS板和GW板导热系数分别增加604%，667%和846%.对于HS板，当含水率<5%时，导热系数增长迅速，当含水率>5%时，导热系数增长缓慢.HS板的导热系数随相对饱和度的增加而逐渐增大，饱和吸水率越大，其导热系数增加越显著.

Abstract:

High performance hollow sphere(HS) boards were prepared using hollow sphere as raw materials. The influence of moisture content on the thermal conductivity of HS boards, expanded polystyrene(EPS) boards and glass wool(GW) boards was investigated. Besides, the effect of saturated water absorption and bulk density on the thermal conductivity of HS boards were systematically studied. The results show that thermal conductivity of samples increases with the increase of moisture content. When moisture content(by mass) is 5%, the growth rate of thermal conductivity of EPS boards, HS boards and GW boards is 604%, 667% and 846%, respectively. For the HS boards, when moisture content is less than 5%, the thermal conductivity increases rapidly; while moisture content is more than 5%, the thermal conductivity increases slowly. Growth rate of thermal conductivity of HS boards increases with the increase of relative saturation, thermal conductivity increases the more significantly especially for the higher water absorption samples.