Abstract
We report experiments on bubble formation from needles with and without liquid co-flow, carried out with needles in the range of 0.79<dn<2.06 mm, for gas flow rates up to 4.5 cm3/s per needle, and with liquid co-flow velocities up to 0.4 m/s. Bubble sizes and frequencies were obtained by means measuring an acoustic signal in the pressurized chamber upstream, which is validated by high-speed imaging analysis. Bubble contours, bubble growth curves and time return plots were obtained to analyse the bubble formation process. Different bubbling regimes are distinguished and a novel dimensionless pressure ratio is proposed to forecast the emergence of weeping and the transition from constant flow rate bubbling to constant chamber pressure bubbling. A single correlation for the non-dimensional bubble size with and without liquid co-flow was developed and validated with the experimental data obtained in the present study.
Original language | English |
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Pages (from-to) | 318-335 |
Number of pages | 18 |
Journal | Chemical Engineering Science |
Volume | 202 |
DOIs | |
Publication status | Published - 20 Jul 2019 |
Keywords
- Acoustic signal
- Bubble formation
- Image analysis
- Liquid co-flow
- Orifice constant
- Period-2 bubbling