Terminal velocity VTof a single bubble rising through an infinite stagnant liquid in surface tension force dominant regime was investigated theoretically and experimentally. A theoretical VTmodel, which is applicable to a distorted spheroidal bubble with a high bubble Reynolds number, was deduced from a jump condition and a potential flow theory for a flow about an oblate spheroid. Experiments were conducted using air and water to measure bubble trajectories, shapes and velocities. As a result, it was confirmed that (1) the primal cause of widely scattered VTin this regime is not surfactant concentration but initial shape deformation, (2) small initial shape deformation results in a low VTand a high aspect ratio, whereas large initial shape deformation results in a high VTand a low aspect ratio, (3) the primal role of surfactants in this regime is to cause the damping of shape oscillation, by which a contaminated bubble behaves as if it were a clean bubble with low initial shape deformation, and (4) the proposed model gives good predictions of VTfor single distorted bubbles. © 2002 Elsevier Science Ltd. All rights reserved.
All Science Journal Classification (ASJC) codes
- Mechanical Engineering
- Physics and Astronomy(all)
- Fluid Flow and Transfer Processes
Tomiyama, A., Celata, G. P., Hosokawa, S., & Yoshida, S. (2002). Terminal velocity of single bubbles in surface tension force dominant regime. International Journal of Multiphase Flow, 28(9), 1497 - 1519. https://doi.org/10.1016/S0301-9322(02)00032-0