International Journal of Air-Conditioning and Refrigeration

The Society of Air-Conditioning and Refrigerating Engineers of Korea (대한설비공학회)
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Transition of Rivulet Flow from Linear to Droplet Stream

  • Kim, Ho-Young (Thermal/Flow Control Research Center, KIST) ;
  • Kim, Jin-Ho (Building Energy Research Team, KIER) ;
  • Kang, Byung-Ha (School of Mechanical and Automotive Engineering, Kookmin University) ;
  • Lee, Seung-Chul (Department of Automotive Engineering, College of Engineering, Donghae University) ;
  • Lee, Jae-Heon (Department of Mechanical Engineering, College of Engineering, Hanyang University)
  • Published : 2002.09.01
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Abstract

When a liquid is supplied through a nozzle onto a relatively non-wetting inclined solid surface, a narrow rivulet forms. There exist several regimes of rivulet flow depending on various flow conditions. In this paper, the fundamental mechanism behind the transition of a linear rivulet to a droplet flow is investigated. The experiments show that the droplet flow emerges due to the necking of a liquid thread near the nozzle. Based on the observation, it is argued that when the retraction velocity of a liquid thread exceeds its axial velocity, the bifurcation of the liquid thread occurs, and this argument is experimentally verified.

Keywords

References

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