Dynamics of bubble breakup at a T junction
Yutao Lu1, Taotao Fu1, Chunying Zhu1
1State Key Laboratory of Chemical Engineering, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China.
Physical Review. E
|March 18, 2016
Summary
Researchers studied bubble breakup in T junctions, identifying two distinct regimes: fast, irreversible breakup driven by surface tension and inertia, and slow, reversible breakup influenced by the continuous phase. A critical bubble neck width determines breakup dynamics.
Area of Science:
- Fluid Dynamics
- Interfacial Phenomena
- Multiphase Flow
Background:
- Bubble breakup in T junctions is crucial for multiphase flow processes.
- Understanding interfacial dynamics is key to predicting flow behavior.
Purpose of the Study:
- Investigate the gas-liquid interfacial dynamics during bubble breakup in a T junction.
- Characterize different bubble breakup regimes and their governing mechanisms.
Main Methods:
- Utilized stop-flow technique to analyze bubble neck evolution.
- Observed and categorized four distinct breakup regimes.
- Quantified bubble neck width and depression region changes over time.
Main Results:
- Identified a critical bubble neck width determining breakup reversibility.
- Fast breakup (neck width < critical) is inertia and surface tension-driven.
- Slow breakup (neck width > critical) is driven by the continuous phase and involves equilibrium stages.
- Bubble neck width scales with time via power laws (0.22 and 0.5) during fast breakup.
- Depression region width follows power law (0.75) and logarithmic functions during slow breakup.
Conclusions:
- Bubble breakup in T junctions exhibits distinct regimes based on neck width.
- Surface tension, liquid inertia, and continuous phase dynamics govern breakup speed and reversibility.
- Mathematical scaling laws describe bubble neck and depression evolution during breakup.
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