Modelling of the Bubble Size Distribution in an Aerated Stirred Tank: Theoretical and Numerical Comparison of Different Breakup Models

• Authors: Zbyněk Kálal , Milan Jahoda , Ivan Fořt
• Languages of publication: EN

Abstracts

EN

The main topic of this study is the mathematical modelling of bubble size distributions in an aerated stirred tank using the population balance method. The air-water system consisted of a fully baffled vessel with a diameter of 0.29 m, which was equipped with a six-bladed Rushton turbine. The secondary phase was introduced through a ring sparger situated under the impeller. Calculations were performed with the CFD software CFX 14.5. The turbulent quantities were predicted using the standard k-ε turbulence model. Coalescence and breakup of bubbles were modelled using the MUSIG method with 24 bubble size groups. For the bubble size distribution modelling, the breakup model by Luo and Svendsen (1996) typically has been used in the past. However, this breakup model was thoroughly reviewed and its practical applicability was questioned. Therefore, three different breakup models by Martínez-Bazán et al. (1999a, b), Lehr et al. (2002) and Alopaeus et al. (2002) were implemented in the CFD solver and applied to the system. The resulting Sauter mean diameters and local bubble size distributions were compared with experimental data.

Keywords

EN

CFD; mixing; gas-liquid; population balance; bubble breakup

• Publisher: De Gruyter Open
• Journal: Chemical and Process Engineering
• Year: 2014
• Volume: 35
• Issue: 3
• Pages: 331-348

Dates

published

1 - 9 - 2014

online

17 - 10 - 2014

received

30 - 1 - 2014

accepted

30 - 5 - 2014

revised

8 - 5 - 2014

Contributors

author

Zbyněk Kálal

• Institute of Chemical Technology, Prague, Technická 5, 166 28 Prague 6, Czech Republic

author

Milan Jahoda

• Institute of Chemical Technology, Prague, Technická 5, 166 28 Prague 6, Czech Republic 2

author

Ivan Fořt

• Czech Technical University in Prague, Technická 4, 166 07 Prague 6, Czech Republic

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Identifiers

DOI

10.2478/cpe-2014-0025