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

The Society of Air-Conditioning and Refrigerating Engineers of Korea (대한설비공학회)
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Effects of Discrete Ribs on Pressure Drop in a Rotating Two-Pass Duct

단락요철이 회전덕트 내 압력강하에 미치는 영향

  • Kim Kyung-Min (Graduate School of Mechanical Engineering, Yonsei University) ;
  • Lee Dong-Hyun (Graduate School of Mechanical Engineering, Yonsei University) ;
  • Cho Hyung-Hee (School of Mechanical Engineering, Yonsei University)
  • 김경민 (연세대학교 대학원 기계공학부) ;
  • 이동현 (연세대학교 대학원 기계공학부) ;
  • 조형희 (연세대학교 기계공학부)
  • Published : 2006.05.01
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Abstract

The present study has been conducted to investigate the effects of rotation on heat/mass transfer and pressure drop characteristics in a two-pass square duct with and without discrete ribs. For stationary cases, the heat/mass transfer on the surfaces with and without discrete ribs is almost the same or reduced. For rotating cases, the gap flow affects differently the heat/mass transfer on leading and trailing surfaces with discrete ribs. On the leading surface of the first pass, the heat/mass transfer is slightly enhanced due to generating strong gap flow. On the trailing surface of the first pass, however, the heat/mass transfer is much decreased because the gap flow disturbs impingement of main flow. The phenomenon, that is, the heat/mass transfer discrepancy between the leading and trailing surfaces is distinctly presented with the increment of rotation number. The friction losses on each surface with discrete ribs are reduced because the blockage ratio decreases for both non-rotating and rotating cases. Therefore, high thermal performance appears in a duct with discrete ribs.

Keywords

References

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