侧风道对多孔保温材料内水分迁移特性的影响规律研究  

Influence of Wind Channel on Moisture Migration Characteristics in Porous Thermal Insulation Material

作　　者：陈燕地 张婉雨 张良俊 李春煜 吴静怡[1] 杨光[1] CHEN Yandi;ZHANG Wanyu;ZHANG Liangjun;LI Chunyu;WU Jingyi;YANG Guang(Institute of Refrigeration and Cryogenics,Shanghai Jiao Tong University,Shanghai 200240,China;Shanghai Key Laboratory of Spacecraft Mechanism,Shanghai 201108,China)

机构地区：[1]上海交通大学制冷与低温工程研究所,上海200240 [2]上海市空间飞行器机构重点实验室,上海201108

出　　处：《真空与低温》2023年第3期251-260,共10页Vacuum and Cryogenics

基　　金：上海市空间飞行器机构重点实验室开放课题(18DZ2272200)。

摘　　要：以露点温度为-50℃的多孔保温材料的干燥除湿过程为研究对象,针对其在对流干燥工况下的水分迁移特性开展数值模拟,并进行实验验证;获得了不同入口压力、入口温度、风道宽度以及保温层厚高比对于干燥过程的影响规律。研究结果表明,Darcy扩展模型可以有效地反映多孔保温材料内部水蒸气的迁移过程。提高入口压力可以提高水分迁移效率,有利于加快干燥过程。入口温度对于水分迁移的影响并不明显,其作用体现在对浮升力的影响。对于特定的多孔保温材料,存在一个临界的厚高比,即高于该临界值时,侧风道会增加整体的干燥时间;而低于该临界值时,侧风道会减少整体的干燥时间。对于孔隙率为70.8%的珠光砂,临界厚高比为0.09。The present study took the drying process of porous thermal insulation material for dew-point temperature of -50℃ as the object.The simulation analysis and experimental verification were carried out for its moisture migration characteristics under convective drying conditions.The quantitative effects of inlet pressure,inlet temperature,wind channel width and insulation layer aspect ratio on the drying process were obtained.The results show that the extended Darcy’s Law can effectively reflect the water vapor migration process in porous thermal insulation materials.Increasing the inlet pressure can improve the water transfer efficiency and accelerate the drying process.The effect of inlet temperature on the results is not obvious,and its effect is reflected in the effect of buoyancy.For specific porous insulation materials,there is a critical aspect ratio,above which the wind channel will increase the overall drying time.Below this critical value,the wind channel reduces the overall drying time.For pearlite with porosity of 70.8%,the critical aspect ratio is 0.09.

关 键 词：多孔材料 Darcy渗流 对流干燥 低温绝热 

分 类 号：TB61[一般工业技术—制冷工程]