71th Annual Meeting of the APS Division of Fluid Dynamics (November 18, 2018 — November 20, 2018)

P0010: Vital eruption: particle-laden bubbly jetting wake from vitamin pills

Authors

• Sohyun Jung, Department of Mechanical and Aerospace Engineering, Seoul National University, Korea
• Wonjung Kim, Department of Mechanical Engineering, Sogang University, Korea
• Hyungmin Park, Department of Mechanical and Aerospace Engineering, Seoul National University, Korea
• Ho-Young Kim, Department of Mechanical and Aerospace Engineering, Seoul National University, Korea

DOI: https://doi.org/10.1103/APS.DFD.2018.GFM.P0010

Effervescent vitamin pills, mostly shaped like a thick disk, are designed to dissolve in water as compounds of powdered vitamin and sodium hydrogen carbonate. When the pill is introduced into flowing water, the dissolution of sodium hydrogen carbonate forms bubbles along with detachment of the fragmented vitamin. The rise of bubbles accompanies the vitamin particles as well as the surrounding liquid, to form particle-laden bubbly jets. We visualize the three-phase flow, a consequence of the interaction of the bubbly jets and the wake of free-stream, to reveal that the secondary flows behind the pill rotate in a direction opposite to that of the normal wake of a single-phase flow behind a bluff body. The recirculation of the bubbles and particles explosively emitted from the effervescent vitamin pill is reminiscent of a volcanic ash eruption.