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

  • 제29권4호
  • /
  • Pages.149-158
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  • 2017
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  • 1229-6422(pISSN)
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  • 2465-7611(eISSN)
대한설비공학회 (The Society of Air-Conditioning and Refrigerating Engineers of Korea)
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외기 온도 변화가 핀-관 열교환기의 공기측 열전달계수와 마찰계수에 미치는 영향에 관한 실험적 연구

An Experimental Study on the Effect of the Air Temperature on the Air-Side Heat-Transfer Coefficient and the Friction Factor of a Fin-and-Tube Heat Exchanger

  • 김내현 (인천대학교 기계시스템공학부) ;
  • 조홍기 (삼성전자 생활가전사업부)
  • Kim, Nae-Hyun (Division of Mechanical System Engineering, Incheon National University) ;
  • Cho, Honggi (Digital Appliance Business, Samsung Electronics)
  • 투고 : 2016.11.07
  • 심사 : 2016.12.05
  • 발행 : 2017.04.10
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초록

In general, the air-side j and f factors of evaporators or condensers are obtained through single-design tests performed under air-dry and wet-bulb temperatures. Considering that the indoor or outdoor air temperatures vary significantly during the operation of an air conditioner, it is necessary to confirm that the experimentally-obtained j and f factors are widely applicable under variable air conditions. In this study, a series of tests were conducted on a two-row slit-finned heat exchanger to confirm the applicability. The results showed that, for the dry-surface condition, the changes of the tube-side water temperature, water-flow rate, and air temperature had virtually no effect on the air-side j and f factors. For the wet condition, however, the f factor was significantly affected by these changes; contrarily, the j factor is relatively independent regarding this change. The formulation of the possible reasoning is in consideration of the condensation behavior underneath the tube. The wet-surface j and f factors are larger than those of the dry surface, with a larger amount for the f factor.

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참고문헌

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