LIU Xin, ZHANG Yu, ZHANG Li, et al. Hydrodynamics simulation of pressurized bubble column based on bubble swarm interphase force models[J]. CIESC Journal, 2017, (1): 87-96.
DOI:
LIU Xin, ZHANG Yu, ZHANG Li, et al. Hydrodynamics simulation of pressurized bubble column based on bubble swarm interphase force models[J]. CIESC Journal, 2017, (1): 87-96.DOI: 10.11949/j.issn.0438-1157.20160762.
Hydrodynamics simulation of pressurized bubble column based on bubble swarm interphase force models
The commercial bubble column reactors are normally operated under the conditions of pressurized state and churn turbulent bubbly flow which the superficial gas velocity always exceeded 0.1 m·s-1.However
most of the published literatures are focus on the cold model experimental investigation of the flow field characteristics in pressurized churn-turbulent bubble columns
and the empirical or semi-empirical correlations which were on the basis of the cold model experimental data to quantitatively estimate the characteristic parameters.Therefore
it is lack of the systematic study on the flow characteristics in the pressurized turbulent bubble columns by the hydrodynamic models with interactions between bubbles and liquid phase.In this work
a steady 2-D axisymmetric hydrodynamic two-fluid model of pressurized bubble column was developed on the platform of FLUENT 15.0 with the UDF sub-models which described the bubble swarm interface forces.The numerical investigations upon the flow field characteristics of pressurized churn turbulent bubble column with the operation pressure varying from 0.5 MPa to 2.0 MPa
and superficial gas velocity from 0.2 m·s-1 to 0.31 m·s-1 were performed.Moreover
the comparisons between the simulation results and cold model experimental data were implemented.The comparisons indicated that
the model with the bubble swarm interface forces including improved bubble swarm drag force model
lateral force balance model
and wall lubrication force model
is able to reflect the influences of operation pressure and superficial gas velocity upon flow pattern
that is
the elevating operation pressure leads to increase of time averaged gas holdup and decrease of time averaged axial gas phase velocity
whereas for the ascending superficial gas velocity
the gas holdup and gas phase velocity are both raising.Consequently this mathematical model could correctly predict the basic gas-liquid flow pattern in the turbulent pressurized bubble columns
and simulation results are in good agreement with the experimental data.