Journal of the Korea Academia-Industrial cooperation Society (한국산학기술학회논문지)

The Korea Academia-Industrial cooperation Society (한국산학기술학회)
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Performance Comparison between Indirect Evaporative Coolers made of Aluminum, Plastic or Plastic/Paper

알루미늄, 플라스틱, 플라스틱/종이 재질의 간접 증발 소자 성능 비교

  • Kim, Nae-Hyun (Division of Mechanical System Engineering Incheon National University)
  • 김내현 (인천대학교 기계시스템공학부)
  • Received : 2015.06.22
  • Accepted : 2015.12.04
  • Published : 2015.12.31
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Abstract

In Korea, summer is hot and humid, and air-conditioners consume lots of electricity. In such case, simultaneous usage of indirect evaporative cooler may reduce the sensible heat and save the electricity. In this study, heat transfer and pressure drop characteristics of indirect evaporative cooler made of aluminum, plastic, plastic/paper are investigated both under dry or wet condition. Results show that indirect evaporation efficiencies of the plastic/paper sample (38.5% ~ 51.4%) are approximately the same as those of the aluminum sample (41.9% ~ 47.5%), and are larger than those of the plastic sample (29.0% ~ 37.4%). This suggests that the plastic/paper sample could be a good substitute to the aluminum sample. However, the pressure drops across the paper channel are 92% ~ 106% larger than those across the aluminum channel. The heat transfer coefficients of the paper channel under dry condition are 15% ~ 44% larger than those of the plastic channel. The increases are 185% ~ 203% for the aluminum channel. The pressure drops of the paper channel are 34% ~ 48% larger than those of the plastic channel and 93% ~ 106% larger than those of the aluminum channel. Rigorous heat transfer analysis reveals that, for the plastic sample, 30% ~ 37% of the wet channels remain dry, whereas all the channels are wet for plastic/paper sample. For aluminum sample, the ratio is 17% ~ 23%.

여름철이 무더운 대한민국에서는 냉방에 많은 전력을 소비한다. 이 경우 간접증발냉각을 동시에 적용하면 전기 사용을 줄일 수 있다. 본 연구에서는 알루미늄, 플라스틱, 플라스틱/종이 재질로 만들어진 간접증발소자에 대하여 건표면 및 습표면 실험을 수행하였다. 실험 결과 플라스틱/종이 소자의 간접증발효율은 38.5% ~ 51.4%로 알루미늄 소자의 값 (41.9% ~ 47.5%)과 유사하고 플라스틱 소자의 값 (29.0% ~ 37.4%)보다는 높게 나타났다. 이로부터 저가의 플라스틱/종이 재질의 간접증발소자가 고가의 알루미늄 재질 간접증발소자를 대체할 수 있으리라 판단된다. 하지만 종이 채널의 압력손실은 알루미늄 채널의 압력손실보다 92% ~ 106% 크다. 한편 종이와 알루미늄 건채널의 열전달계수는 플라스틱 건채널의 값보다 15% ~ 44%, 185% ~ 203% 크게 나타났다. 반면 종이 건채널의 압력손실은 알루미늄 건채널 보다 93% ~ 106%, 플라스틱 건채널보다 34% ~ 48% 크게 나타났다. 습표면 해석결과 알루미늄 습채널에서는 17% ~ 23%, 플라스틱 습채널에서는 30% ~ 37%가 건표면으로 나타났다. 반면 종이 습채널의 경우는 100% 습표면으로 나타났다. 이는 종이의 흡습성이 알루미늄이나 플라스틱보다 월등하기 때문이다.

Keywords

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