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Heat and Mass Transfer

, Volume 43, Issue 8, pp 787–799 | Cite as

A CFD comparative study of bubble break-up models in a turbulent multiphase jet

  • J. M. Martín-ValdepeñasEmail author
  • M. A. Jiménez
  • R. Barbero
  • F. Martín-Fuertes
Original

Abstract

In this paper several bubble break-up models are compared. They have been implemented in the CFX-4.4 fluid dynamic commercial code, which uses the population balance equations for describing liquid/gas multi-phase flows. The models have been assessed against published experimental data, obtained for air bubble break-up within a turbulent water jet. The model of Martínez-Bazán, based on purely kinematics arguments, has shown better agreement with the experimental data. The capabilities of using these models coupled to a CFD code for multiphase flow prediction in industrial applications have been demonstrated.

Keywords

Bubble Size Nozzle Diameter Computational Fluid Dynamic Code Bubble Size Distribution Population Balance Equation 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

List of symbols

CD

drag coefficient

CTD

turbulent dispersion coefficient

Cpdf

cumulative volume probability density function

dB

local bubble mean diameter (m)

D

nozzle diameter (m)

De

eddy size in the inertial sub-range (m)

fi

volume fraction of bubbles in the i-th group (f i  =  r i /r g)

f

particle size distribution (m−1) or (m−3)

F

inter-phase momentum transfer (N m−3)

g

break-up frequency (s−1)

ni

number of bubbles in the i-th group per unit volume (m−3)

r

volume fraction of the phase

ReD

Reynolds number at the nozzle section \(\left(Re _{D} = \frac{{\rho _{l} U_{0} D}}{\mu }\right)\)

u

velocity of the phase (m s−1)

U

mean axial velocity of the single phase jet (m s−1)

UC

mean axial velocity at the jet axis (m s−1)

U0

mean axial velocity at the nozzle section (ms−1)

vi

volume of the bubbles in the i-th group (m3)

X

axial distance to the jet nozzle section (m)

Greek letters

ɛ

dissipation rate of turbulent energy (m2 s−3)

μ

dynamic viscosity (Pa s)

ρ

density of the phase (kg m−3)

σ

surface tension (N m−2)

Subscripts

c

critical bubble

g

gas phase

i

bubble size

k

phase k

l

liquid phase

m

m-th phase

0

mother bubble

1

first daughter bubble

2

complementary daughter bubble

Superscripts

D

drag term

T

turbulent term

Notes

Acknowledgments

Authors wished to acknowledge the support from the Fifth Framework Program of the European Commission under the Energy, Environment and Sustainable Development Contract EVG1-CT-2001-00042 (EXPRO). Moreover, authors wished to thank Mr. Francisco Herráez for his assistance in the simulations.

References

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Copyright information

© Springer-Verlag 2006

Authors and Affiliations

  • J. M. Martín-Valdepeñas
    • 1
    Email author
  • M. A. Jiménez
    • 1
  • R. Barbero
    • 1
  • F. Martín-Fuertes
    • 1
  1. 1.College of Industrial Engineering, Department of Nuclear EngineeringUniversidad Politécnica de MadridMadridSpain

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