摘要
空气源热泵机组除霜过程主要包括融霜、排水、蒸干等环节。以上环节在不同浸润性换热器翅片表面上表现不尽相同,从而直接影响机组在周期性结除霜工况下的运行性能。本文搭建了金属冷表面除霜特性研究实验台,分别以普通和亲水铝箔为研究对象,观察分析霜层的融化、化霜水排除以及蒸干过程,并着重对比了两种常用铝箔翅片在上述过程的差异。首次提出"翅片表面蒸干率"的概念,用参数C表示;研究发现,普通铝箔表面初始蒸干率即可达到90%,而亲水铝箔表面仅50%;但亲水铝箔表面残留水完全蒸干所用时间仅需7 min,仅为普通铝箔表面完全蒸干时间的25%;两种铝箔除霜过程差异显著。研究工作同时考察了残留水对相邻结除霜过程的影响。
The defrost process of air source heat pump （ASHP） includes melting, drainage and evaporation. The characteristics of above processes are different for the heat exchanger fin surfaces with different wettabilities, which greatly influences the performance of ASHP units during the periodic frosting-defrosting cycles. In this paper, an experimental system was built to study the characteristics of defrost, drainage and evaporation processes on different surfaces, such as hydrophilic and common aluminum foil surfaces. The concept of “fin surface evaporation ratio”was proposed in this paper, which was abbreviated as C. It was found that, the initial value of C can get up to 90% on common aluminum foil surface, and 50% on the hydrophilic aluminum foil surface. However, it takes only 7 minutes to evaporate the defrosting water completely for hydrophilic aluminum foil surface, which is 25% of that for the common aluminum foil surface. The defrost processes for two kind of aluminum foils are significantly different with each other. The effects of defrosting water retention on the next frosting-defrosting process were also investigated.
出处
《制冷技术》
2014年第1期26-31,共6页
Chinese Journal of Refrigeration Technology
基金
北京市教委科技计划面上项目(KM201210005026)
北京市青年拔尖人才培养计划(201304047)
关键词
亲水铝箔
普通铝箔
霜层
融霜
蒸干率
Hydrophilic aluminum foil
Common aluminum foil
Frost layer
Defrost
Fin surface evaporation ratio
