[1]郝英立,Jose IragorryY,ong X. Tao.壁面结霜初始状态实验研究[J].东南大学学报(自然科学版),2005,35(1):149-153.[doi:10.3969/j.issn.1001-0505.2005.01.032]
 Hao Yingli,Jose Iragorry,Yong X. Tao.Experimental study of initial state of frost formation on flat surface[J].Journal of Southeast University (Natural Science Edition),2005,35(1):149-153.[doi:10.3969/j.issn.1001-0505.2005.01.032]
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壁面结霜初始状态实验研究()
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《东南大学学报(自然科学版)》[ISSN:1001-0505/CN:32-1178/N]

卷:
35
期数:
2005年第1期
页码:
149-153
栏目:
能源与动力工程
出版日期:
2005-01-20

文章信息/Info

Title:
Experimental study of initial state of frost formation on flat surface
作者:
郝英立1Jose Iragorry2Yong X. Tao2
1 东南大学动力工程系, 南京 210096; 2 佛罗里达国际大学机械与材料工程系, 迈阿密, FL 33174
Author(s):
Hao Yingli1 Jose Iragorry2 Yong X. Tao2
1 Department of Power Engineering, Southeast University, Nanjing 210096, China
2 Department of Mechanical and Materials Engineering, Florida International University, Miami, FL 33174, USA
关键词:
结霜 结霜临界状态 分形 自然对流
Keywords:
frost frost critical state fractal natural convection
分类号:
TK124
DOI:
10.3969/j.issn.1001-0505.2005.01.032
摘要:
对自然对流条件下干燥和湿润2种初始状况平板表面上的初始结霜现象进行了显微观测.实验结果表明,表面稳定温度愈低,结霜发生愈早,临界温度也愈低.干燥表面上凝结的液滴及随后冻结的冰粒形状较湿润表面的规整且接近圆形.干燥表面发生结霜较湿润表面早,其差别随表面稳定温度的降低而减小.表面稳定温度高于-15 ℃时,2类表面的临界温度几乎相同; 随着表面稳定温度降低,干燥表面的临界温度较湿润表面低,其差别随着表面稳定温度的降低而增大.分析表明结霜临界状态时冰粒的大小及其在冷表面上的分布具有分形特征,并提出一基于分形理论定量描述其特征的方法.干燥和湿润2种表面上临界结霜时冰粒的平均直径并无显著差别,而湿润表面上的冰粒表面覆盖率较干燥表面的大.
Abstract:
A microscopic analysis of frost formation on the dry/wet flat surface under natural convection is conducted. The result indicates that the critical time is reached faster and the critical temperature is also lower under the condition of the lower steady-state temperature. The sharp of the droplets/ice particles under the initial condition of the dry surface is more regular(close to the circle)than that under the initial condition of wet surface. The critical time under the initial condition of dry surface is reached earlier than that under the initial condition of wet surface. The difference decreases with the decrease in the steady-state temperature. The critical temperatures are almost the same for the cases where the steady-state temperature is higher than -15 ℃. The critical temperature under the initial condition of dry surface is lower than that under the initial condition of wet surface in the cases where the steady-state temperature is lower than -15 ℃. For that case, the difference increases with the decrease of the steady-state temperature. The sizes and distributions of droplets/ice particles show fractal characteristics. A method based on the fractal analysis is proposed to quantitatively determine the characteristic sizes and distributions of droplets/ice particles during the onset of freezing when sub-cooled droplets are formed and changed to the ice particles. The ice particle fraction on the wet surface is greater than that on the dry surface at the onset of freezing while there is no significant difference on the mean diameter of ice particles on both.

参考文献/References:

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相似文献/References:

[1]郝英立,Jose Iragorry,Yong X. Tao.初始成长阶段霜层特性实验研究[J].东南大学学报(自然科学版),2005,35(1):154.[doi:10.3969/j.issn.1001-0505.2005.01.033]
 Hao Yingli,Jose Iragorry,Yong X. Tao.Experimental investigation on characteristics of frost layer during the initial growth period[J].Journal of Southeast University (Natural Science Edition),2005,35(1):154.[doi:10.3969/j.issn.1001-0505.2005.01.033]

备注/Memo

备注/Memo:
基金项目: 东南大学科学基金资助项目(9203007013).
作者简介: 郝英立(1963—),男,博士,教授,haoy@seu.edu.cn.
更新日期/Last Update: 2005-01-20