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

The Korean Society of Mechanical Engineers (대한기계학회)
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Flow Condensation Inside Mini-Channels (II) -Experimental Study of the Circular and Rectangular Channels-

작은 유로 내에서의 흐름응축 열전달 (II) -원형 및 사각유로에서의 실험적 연구-

  • 신정섭 (한국과학기술원 기계공학과) ;
  • 김무환 (포항공과대학교 기계공학과)
  • Published : 2004.11.01
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Abstract

By using unique experimental techniques and careful construction of the experimental apparatus, the characteristics of the local heat transfer were investigated using the condensing R134a two-phase flow, in horizontal single mini-channels. The circular channels (D$_{h}$=0.493, 0.691, and 1.067 mm) and rectangular channels (Aspect Ratio=1.0, D$_{h}$=0.494, 0.658, and 0.972 mm) were tested and compared. Tests were performed for a mass flux of 100, 200, 400, and 600 kg/$m^2$s, a heat flux of 5 to 20 ㎾/$m^2$, and a saturation temperature of 4$0^{\circ}C$. In this study, effect of heat flux, mass flux, vapor qualities, hydraulic diameter, and channel geometry on flow condensation are investigated and the experimental local condensation heat transfer coefficients are shown. The experimental data of condensation Nusselt number are compared with existing correlations.ons.

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References

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