摘要
利用液氮作冷媒，研究管内含湿空气流动结霜现象。深冷壁面的温度ｔｗ＝７７Ｋ，管内流速ｕ＝５～３０ｍ／ｓ。获得了霜层厚度ｘｓ、霜层密度ρｆ、霜层综合热导率ｋｆ及热阻ｒｆ、霜层表面温度ｔｓ以及流动阻力系数ｆ等参数的变化规律。还观察到了霜体吹动和霜层崩塌现象。本文结果可为结霜理论模型评定和工程设计提供实验依据。
In this paper the phenomena of frost formation inside a tube under forced convection of humid air had been investigated experimentally with LN 2 used as cold medium, cryosurface temperature t w=77K and air velocity u=5～30m/s. The varied relations to such parameters as thickness x s of frost layer, frost density ρ f, effective thermal conductivity k f and resistance r f of frost layer, surface temperature t s of frost layer and flow friction factor f have been obtained. The stirring of frost body and collapse of frost layer had been also observed, The results may offer the experiment basis for the evaluation of theoretical models about frost formation and the engineering design.
出处
《低温工程》
CAS
CSCD
北大核心
1997年第2期10-15,共6页
Cryogenics
关键词
管内流动
结霜
低温
internal tube flow
frost formation
low temperature
experimantal research
