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 Evaporation Water Flow Rate on the Performance of an Indirect Evaporative Cooler

증발수 유량이 간접 증발식 냉각기 성능에 미치는 영향

  • Choo, Hyun-Seon (Department of Mechanical Engineering, Graduate School, Hanyang University) ;
  • Lee, Kwan-Soo (Department of Mechanical Engineering, Hanyang University) ;
  • Lee, Dea-Young (Korea Institute of Science & Technology)
  • 추현선 (한양대학교 대학원) ;
  • 이관수 (한양대학교 공과대학 기계공학부) ;
  • 이대영 (한국과학기술연구원 열.유동제어센터)
  • Published : 2006.09.01
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Abstract

In evaporative cooling applications, the evaporation water is supplied usually sufficiently larger than the amount evaporated to enlarge contact surface between the water and the air. Especially in indirect evaporative coolers, however, if the evaporation water flow rate is excessively large, the evaporative cooling effect is not used for heat absorption from the hot fluid but spent to the sensible cooling of the evaporation water itself. This would result in a decrease in the cooling performance of the indirect evaporative cooler. In this study, the effects of the evaporation water flow rate on the cooling performance are investigated theoretically. The cooling process in an indirect evaporative cooler is modeled into a set of linear differential equations and solved to obtain the exact solutions to the temperatures of the hot fluid, the moist air, and the evaporation water. Based on the exact solutions, it is analyzed how much the cooling performance is affected by the evaporation water flow rate. The results show that the decrease in the cooling effectiveness is substantial even for a small flow rate of the evaporation water and the relative decrease is more serious for a high-performance evaporative cooler.

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References

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