Journal of the Korean Society of Visualization (한국가시화정보학회지)

The Korean Society of Visualization (한국가시화정보학회)
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Relationship between void fraction and mixing in bubble column flow

기포탑 유동에서의 기포분율과 혼합정도의 상관관계

  • Zahidul, Islam MD (Department of Mechanical & Aerospace Engineering, Seoul National University) ;
  • Lee, Jubeom (Department of Mechanical & Aerospace Engineering, Seoul National University) ;
  • Park, Hyungmin (Department of Mechanical & Aerospace Engineering, Seoul National University)
  • Received : 2017.04.02
  • Accepted : 2017.04.19
  • Published : 2017.04.30
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Abstract

Control of mixing and transport processes are the key areas that can be benefited by understanding the hydrodynamics in gas-liquid two-phase flows. In particular, the enhanced bubble-induced liquid-phase mixing is known to be a function of void fraction distribution, gas phase velocity and so on. To further our insight on the characteristics of the liquid-phase mixing induced by the bubbles, in the present study, we experimentally investigate the mixing performance of a rectangular bubble column while changing the void fraction from 0.006 to 0.075%. A shadowgraphy technique is used to measure the gas-phase properties such as void fraction and size/velocity of bubbles. On the other hand, we use dye visualization with low diffusive buoyant dye to directly measure the level of mixing. Finally, we confirm that the time taken for full mixing scales with the inverse of volume void fraction.

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References

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