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

The Society of Air-Conditioning and Refrigerating Engineers of Korea (대한설비공학회)
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Cooling Performance of a Counterflow Regenerative Evaporative Cooler with Finned Channels

대향류 핀삽입형 재생증발식 냉방기의 냉방성능

  • Moon, Hyun-Ki (Energy Mechanics Research Center, Korea Institute of Science & Technology) ;
  • Lee, Dae-Young (Energy Mechanics Research Center, Korea Institute of Science & Technology)
  • 문현기 (한국과학기술연구원 에너지메카닉스 연구센터) ;
  • 이대영 (한국과학기술연구원 에너지메카닉스 연구센터)
  • Published : 2008.07.10
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Abstract

A regenerative evaporative cooler has been fabricated and tested for the evaluation of cooling performance. The regenerative evaporative cooler is a kind of indirect evaporative cooler comprised of multiple pairs of dry and wet channels. The air flowing through the dry channels is cooled without any change in the humidity and at the outlet of the dry channel a part of air is redirected to the wet channel where the evaporative cooling takes place. The regenerative evaporative cooler fabricated in this study consists of the multiple pairs of finned channels in counterflow arrangement. The fins and heat transfer plates were made of aluminum and brazed for good thermal connection. Thin porous layer coating was applied to the internal surface of the wet channel to improve surface wettability. The regenerative evaporative cooler was placed in a climate chamber and tested at various operation condition. The cooling performance is found greatly influenced by the evaporation water flow rate. To improve the cooling performance, the evaporation water flow rate needs to be minimized as far as the even distribution of the evaporation water is secured. At the inlet condition of $32^{\circ}C$ and 50%RH, the outlet temperature was measured at $22^{\circ}C$ which is well below the inlet wet-bulb temperature of $23.7^{\circ}C$.

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References

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