대한기계학회논문집B (Transactions of the Korean Society of Mechanical Engineers B)

  • 제34권12호
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  • Pages.1111-1119
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  • 2010
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  • 1226-4881(pISSN)
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  • 2288-5324(eISSN)
대한기계학회 (The Korean Society of Mechanical Engineers)
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종횡비가 다른 납작관 내 응축열전달 및 압력손실

Condensation Heat Transfer and Pressure Drop in Flat Tubes with Different Aspect Ratios

  • 김내현 (인천대학교 기계시스템공학부) ;
  • 박지훈 (인천대학교 기계시스템공학부) ;
  • 차상진 (인천대학교 기계시스템공학부)
  • Kim, Nae-Hyun (Dept. of Mechanical System Engineering, Univ. of Incheon) ;
  • Park, Ji-Hoon (Dept. of Mechanical System Engineering, Univ. of Incheon) ;
  • Cha, Sang-Jin (Dept. of Mechanical System Engineering, Univ. of Incheon)
  • 투고 : 2010.07.29
  • 심사 : 2010.09.27
  • 발행 : 2010.12.01
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초록

본 연구에서는 내경 5.0mm 원관을 납작하게 한 납작관에 대하여 R-410A 를 사용하여 응축열전달 실험을 수행하였다. 실험은 포화온도와 열유속을 각각 $45^{\circ}C$ 와 10kW/$m^2$으로 고정한 상태에서 질량유속과 건도를 변화시키며 수행되었다. 실험결과 납작관의 종횡비가 열전달계수에 미치는 영향은 유동양식에 따라 달리 나타났다. 환상류에서는 종횡비가 증가할수록 증가하고 성층류에서는 종횡비가 증가할수록 감소하였다. 한편 납작관의 마찰손실은 종횡비가 증가할수록 증가하였다. 기존 상관식들은 납작관의 열전달계수와 마찰계수를 적절히 예측하였다.

In this study, condensation heat transfer coefficients of R-410A were obtained in flattened tubes made from round tubes with an inner diameter of 5.0 mm. The saturation temperature was $45^{\circ}C$; the heat flux, 10 kW/$m^2K$; the mass flux, 100-400 kg/$m^2s$; and the quality, 0.2-0.8. The results showed that the effect of the aspect ratio on the condensation heat transfer coefficient depended on the flow pattern. For annular flow, the heat transfer coefficient increased as the aspect ratio increased. For stratified flow, however, the reverse was true: the pressure drop increased as the aspect ratio increased. Existing correlations adequately predicted the heat transfer coefficients and pressure drops of the flattened tubes.

키워드

참고문헌

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피인용 문헌

  1. Effect of Aspect Ratio of Flat Tube on R410A Evaporation Heat Transfer and Pressure Drop vol.37, pp.4, 2013, https://doi.org/10.3795/KSME-B.2013.37.4.395