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

The Korean Society of Mechanical Engineers (대한기계학회)
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An Experimental Study on Heat Transfer of a Falling Liquid Film in Air Channel Flow

채널내 공기유동이 있는 유하액막의 열전달특성에 관한 실험적 연구

  • 오동은 (국민대 대학원 기계공학과) ;
  • 강병하 (국민대학교 기계.자동차 공학부) ;
  • 김석현 (국민대 기계.자동차 공학부) ;
  • 이대영 (KIST 에너지메카닉스 연구센터)
  • Published : 2008.05.01
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Abstract

Thermal transport from vertical heated surface to falling liquid film in a channel has been investigated experimentally. Air-flow is introduced into channel to make a counter flow against falling liquid film. This problem is of particular interest in the design of direct contact heat exchange system, such as cooling tower, evaporative cooling system, absorption cooling system, and distillation system. The effects of channel width and air flow rate on the heat transfer to falling liquid film are studied in detail. The results obtained indicate that heat transfer rate is gradually decreased with an increase in the channel width without air flow as well as with air flow in a channel. It is also found that heat transfer rate of air-flow is increased while heat transfer rate of falling liquid film is decreased with an increase in the air flow rate at a given channel width. However, total heat transfer rate from the heated surface is increased as the air flow rate is increased.

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References

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