Korean Journal of Air-Conditioning and Refrigeration Engineering (설비공학논문집)

The Society of Air-Conditioning and Refrigerating Engineers of Korea (대한설비공학회)
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Effects of Fin Conduction and Superheat Unbalance on the Performance of an Evaporator

핀의 전도 열전달 및 과열도 변화에 따른 증발기 성능 특성에 관한 연구

  • Choi Jong Min (Department of Mechanical Engineering, Hanbat National University) ;
  • Kim Yongchan (Department of Mechanical Engineering, Korea University)
  • Published : 2005.03.01
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Abstract

An experimental investigation was executed to determine the capacity degradation due to fin conduction and non-uniform refrigerant distribution in a multi-path evaporator with cross-counter flow. The finned-tube evaporator, which had a three-path and three-depth-row, was tested by controlling inlet quality, exit pressure, and exit superheat for each refrigerant path. The capacity reduction due to superheat unbalance between each path was as much as $25\%$ for non-cutting evaporator, even when the overall evaporator superheat was kept at a target value of $5.6^{\circ}C$. It indicates that the internal heat transfer within the evaporator assembly causes the partial capacity drop. The capacity of cutting-evaporator with respect to non-cutting evaporator was enhanced according to the increment of air flow rate when superheat or superheat unbalance increased.

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References

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