Effect of Wavy Flow of Vertical Falling Film on the Absorption Performance

  • Kim, Jung-Kuk (Graduate School of Mechanical Engineering, Sungkyunkwan University) ;
  • Cho, Keum-Nam (Department of Mechanical Engineering, Sungkyunkwan University)
  • Published : 2005.09.01


The present study investigated experimentally and numerically the enhancement of absorption performance due to the waviness of falling film in the vertical absorber tube. The momentum, energy and mass diffusion equations were utilized to find out temperature and concentration profiles at both the interfaces of liquid solution and refrigerant vapor and the wall. Flow visualization was performed to find out the wetting characteristics of the falling film. The maximum heat transfer coefficient was obtained for the wavy flow using spring as an insert device through both numerical and experimental studies. Based on the numerical and experimental results, the maximum absorption rate was found for the wavy-flow using spring as the insert device. The differences between experimental and analytical results ranged from $5.0\;to\;25\%\;when\;Re_j>100$.



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