Shapes and paths of an air bubble rising inside a liquid are investigated experimentally. About three hundred experiments are conducted in order to generate a phase plot in the Galilei and Eötvös numbers plane, which separates distinct regimes in terms of bubble behaviour. A wide range of the Galilei and Eötvös numbers are obtained by using aqueous glycerol solutions of different concentrations as the surrounding fluid and by varying the bubble size. The dynamics are investigated in terms of shapes, topological changes, and trajectories of the bubbles. Direct numerical simulations are conducted to study the bubble dynamics, which show excellent agreement with the experiments. To the best of our knowledge, this is the first time an experimentally obtained phase plot showing the distinct behaviour of an air bubble rising in a quiescent medium is reported for such a large range of Galilei and Eötvös numbers.
All Science Journal Classification (ASJC) codes
- Computational Mechanics
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering
- Fluid Flow and Transfer Processes