Numerical simulations of bubble formation on submerged orifices: Period-1 and period-2 bubbling regimes

• Published in: Chemical engineering science Vol. 62; no. 24; pp. 7119 - 7132
• Main Authors: Buwa, Vivek V., Gerlach, D., Durst, F., Schlücker, E.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Oxford Elsevier Ltd 01-12-2007; Elsevier
• Subjects: Applied sciences; Bubble; Bubble formation dynamics; Bubbling regimes; Chemical engineering; Dynamic simulation; Exact sciences and technology; Hydrodynamics of contact apparatus; Multiphase flow; Reactors; Volume-of-fluid method; Bubble formation dynamics; Volume-of-fluid method; Dynamic simulation; Bubble; Multiphase flow; Bubbling regimes; Cartography; Prediction; Modeling; Bubbling; Numerical simulation; Coalescence; Dynamic model; Reactor; Submerged orifice
• ISSN: 0009-2509; 1873-4405
• DOI: 10.1016/j.ces.2007.08.061

The process of bubble formation is involved in several gas–liquid reactors and process equipment. It is therefore important to understand the dynamics of bubble formation and to develop computational models for the accurate prediction of the bubble formation dynamics in different bubbling regimes. This work reports the numerical investigations of bubble formation on submerged orifices under constant inflow conditions. Numerical simulations of bubble formation at high gas flow rates, where the bubble formation is dominated by inertial forces, were carried out using the combined level set and volume-of-fluid (CLSVOF) method and the predictions were experimentally validated. Effects of gas flow rate and orifice diameter on the bubbling regimes and in particular, on the transition from period-1 to period-2 bubbling regime (with pairing or coalescence at the orifice) were investigated. Using the simulation data on the transition of bubble formation regimes, the bubble formation regime map constructed using Froude
(
Fr
=
U
O
2
/
gd
O
)
and Bond
(
Bo
=
ρ
l
gd
O
2
/
σ
)
numbers is presented.