Journal of Advanced Marine Engineering and Technology

The Korean Society of Marine Engineering (한국마린엔지니어링학회)
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Study on High Performance and Compact Absorber Using Small Diameter Heat Exchanger Tube

  • Yoon Jung-In (School of Mechanical Engineering, Pukyong National University) ;
  • Phan Thanh Tong (Graduate School, Department of Refrigeration and Air-conditioning Engineering, Pukyong National University) ;
  • Moon Choon-Geun (School of Mechanical Engineering, Pukyong National University) ;
  • Kim Eun-Pil (School of Mechanical Engineering, Pukyong National University) ;
  • Kim Jae-Dol (Department of Environemntal Equipment Engineering, Tongmyong University) ;
  • Kang Ki-Cheol (Donghwa Air-conditioning Co., Ltd.)
  • Published : 2006.05.01
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Abstract

The effect of tube diameter on heat and mass transfer characteristics of absorber in absorption chiller/heater using LiBr solution as a working fluid has been investigated by both of numerical and experimental study to develop a high performance and compact absorber. The diameter of the heat exchanger tube inside absorber was changed from 15.88mm to 12.70mm and 9.52mm. In numerical study a model of vapor pressure drop inside tube absorber based on a commercial 20RT absorption chiller/heater was performed. The effect of tube diameter, longitudinal pitch, vapor Reynolds number, longitudinal pitch to diameter ratio on vapor pressure drop across the heat exchanger tube banks inside absorber have been investigated and found that vapor pressure drop decreases as tube diameter increases, longitudinal pitch increases, vapor Reynolds number decreases and longitudinal pitch to diameter ratio increases. In experimental study, a system includes a tube absorber, a generator, solution distribution system and cooling water system was set up. The experimental results shown that the overall heat transfer coefficient, mass transfer coefficient. Nusselt number and Sherwood number increase as solution flow rate increases. In both of study cases, the heat and mass transfer performance increases as tube diameter decreases. Among three different tube diameters the smallest tube diameter 9.52mm has highest heat and mass transfer performance.

Keywords

References

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