结霜工况下平行流换热器的换热性能

上海交通大学学报（自然版） ›› 2013, Vol. 47 ›› Issue (04): 674-678.

结霜工况下平行流换热器的换热性能

梁媛媛, 徐博, 陈江平

（上海交通大学制冷与低温研究所，上海 200240）

收稿日期:2012-06-14 出版日期:2013-04-28 发布日期:2013-04-28

Thermal Transfer Performance of Parallel Flow Heat Exchangers under Frost Conditions

LIANG Yuan-Yuan, XU Bo, CHEN Jiang-Ping

（Institute of Refrigeration and Cryogenics, Shanghai Jiaotong University, Shanghai 200240, China)

Received:2012-06-14 Online:2013-04-28 Published:2013-04-28

摘要/Abstract

摘要： 测试了平行流换热器在结霜工况下的换热性能.研究了换热器的换热面积及表面换热效率随霜层厚度的变化，并采用对数平均温差（LMTD）法对结霜状况下霜层表面的换热系数进行了计算.结果显示，当霜层厚度达到0.4 mm时，换热器的换热面积下降18%左右，表面换热效率下降17.42%～24.78%；而换热系数的降低是换热器性能降低的重要因素，试验中换热器的换热系数均下降50%左右，百叶窗的霜堵是导致换热系数降低的主要原因.

关键词: 平行流换热器, 结霜, 换热面积, 表面换热效率, 换热系数

Abstract: The parallel flow heat exchanger’s thermal transfer performance under frost conditions was investigated. The heat transfer area and overall surface efficiency change as the frost grows. The airside heat transfer coefficient was also calculated using logarithmic-mean temperature difference (LMTD) method. The result shows that when the frost thickness grows to 0.4 mm, the heat transfer area decreases by 18%, and the air side surface efficiency decreases by 17.42%~24.78%. Moreover, the reduction of the heat transfer coefficient is an important cause to the decline of heat exchanger performance. The heat transfer coefficient decreases about 50% in the tests, while louver gap blockage mainly contributes to the decrease of heat transfer coefficient.

Key words: parallel flow heat exchanger, frost, heat transfer area, surface efficiency, heat transfer coefficient

中图分类号:

TB 61

梁媛媛, 徐博, 陈江平. 结霜工况下平行流换热器的换热性能[J]. 上海交通大学学报（自然版）, 2013, 47(04): 674-678.

LIANG Yuan-Yuan, XU Bo, CHEN Jiang-Ping. Thermal Transfer Performance of Parallel Flow Heat Exchangers under Frost Conditions[J]. Journal of Shanghai Jiaotong University, 2013, 47(04): 674-678.

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