CFD prediction of gas-liquid flow in an aerated stirred vessel using the population balance model

• Autorzy: Kálal Z. , Jahoda M. , Fořt I.

Identyfikatory

DOI

10.2478/cpe-2014-0005

• Języki publikacji: EN

Abstrakty

EN

The main topic of this study is the experimental measurement and mathematical modelling of global gas hold-up and bubble size distribution in an aerated stirred vessel using the population balance method. The air-water system consisted of a mixing tank of diameter T= 0.29 m, which was equipped with a six-bladed Rushton turbine. Calculations were performed with CFD software CFX 14.5. Turbulent quantities were predicted using the standard k-ε turbulence model. Coalescence and breakup of bubbles were modelled using the homogeneous MUSIG method with 24 bubble size groups. To achieve a better prediction of the turbulent quantities, simulations were performed with much finer meshes than those that have been adopted so far for bubble size distribution modelling. Several different drag coefficient correlations were implemented in the solver, and their influence on the results was studied. Turbulent drag correction to reduce the bubble slip velocity proved to be essential to achieve agreement of the simulated gas distribution with experiments. To model the disintegration of bubbles, the widely adopted breakup model by Luo & Svendsen was used. However, its applicability was questioned.

Słowa kluczowe

EN

CFD; mixing tank; gas-liquid; drag correction; bubble size distribution

PL

CFD; zbiornik mieszający; gaz-ciecz; korekta przeciągania; rozkład wielkości pęcherzyków

• Wydawca: Komitet Inżynierii Chemicznej i Procesowej Polskiej Akademii Nauk
• Czasopismo: Chemical and Process Engineering
• Rocznik: 2014
• Tom: Vol. 35, nr 1
• Strony: 55--73
• Opis fizyczny: Bibliogr. 38 poz., rys.

Twórcy

autor

Kálal Z.

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

autor

Jahoda M.

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

autor

Fořt I.

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

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