摘要
从形核的概念出发,分析了水蒸气在冷面上的结霜并非单纯凝华的原因,对结霜前的微细观结露现象给予了理论解释:水蒸气在零度以下冷面上凝结生成液核的活化率远远大于凝华生成霜核的活化率,所以冷面上最先出现的是水珠。揭示了疏水面抑制结霜的原因,即增大接触角可以提高成核势垒,使新相变得难形成,从而降低新相的活化率。
From the concept of nucleation, the phenomenon of dewing before frosting was theoretically explained. For steam condensing on a cold surface having temperature below 0℃, since the liquid nucleates form with much greater activating rate than the frost nucleates, water drops first appear on the cold surface. The reason that a hydrophobic surface can retard frosting was also revealed. Increase in contact angle may increase the energy obstacle for nucleation, that the new phase difficult to form, causing a reduced activating rate for the new phase.
出处
《工程热物理学报》
EI
CAS
CSCD
北大核心
2003年第2期286-288,共3页
Journal of Engineering Thermophysics
基金
国家教育部留学回国人员科研启动基金资助项目
关键词
结霜
水蒸气
活化率
形核势垒
frosting on a cold surface
hydrophobic surface
activating rate
