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

The Society of Air-Conditioning and Refrigerating Engineers of Korea (대한설비공학회)
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Characteristics on Spray Cooling Performance on the Micro-Porous Coated Surfaces

마이크로다공성 발열체 표면에서의 액체분무 냉각성능 특성

  • Kim Yoon-Ho (Graduate School of Mechanical Engineering, Korea University) ;
  • Choi Chi-Hwan (Graduate School of Mechanical Engineering, Korea University) ;
  • Lee Kyu-Jung (Department of Mechanical Engineering, Korea University)
  • 김윤호 (고려대학교 기계공학과 대학원) ;
  • 최치환 (고려대학교 기계공학과 대학원) ;
  • 이규정 (고려대학교 기계공학과)
  • Published : 2006.04.01
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Abstract

Experiments on evaporative spray cooling on the square plate heaters with plain or micro-porous coated surfaces were performed in this study. Micro-porous coated surfaces were made by using DOM [Diamond particle, Omegabond 101, Methyl-Ethyl-Keton] method. In case of purely air-jet cooling, the micro-porous coating doesn't affect the cooling capacity. In spray cooling three different flow patterns (complete wetting, evaporative wetting, dryout) are observed on both plain and micro-porous coated surfaces. The effects of various operating conditions, such as water flow rate, particle size, and coating thickness were investigated on the micro-porous coated surfaces. It is found that the level of surface wetting is an important factor to determine the performance of spray cooling. It depends on the balance between absorbed liquid amount by capillary force over porosity and the evaporative amount. The micro-porous coated surface has largest cooling capacity, especially in the evaporative wetting zone. It is found that the effects of liquid flow rate and coating thickness are significant in evaporative wetting zone, but are not in complete wetting and dryout zones.

Keywords

References

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