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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)
Publication Information
International Journal of Air-Conditioning and Refrigeration / v.10, no.3, 2002 , pp. 147-152 More about this Journal
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
Rivulet; Necking; Retraction; Contact angle hysteresis;
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