Eulerian multiphase and boiling flows in
STAR-CCM+
Simon Lo
Contents
Validation of the Eulerian multiphase (EMP) model
– Solid-liquid stirred vessel
Interphase mass transfer of chemical species
Granular flow model
Chemical reaction models
Boiling model
Solid-liquid stirred vessel
Solid-liquid system
1ft tank D=H, flat base
single 6blade PBT d=0.5T
C/H=0.25, 4 baffles
Liquid:
Water-salt solution
rl=1150 kg/m3
m=4.5e-3 Pas
H
g
C
Solid:
Glass particles
dp=3.075 mm
rp=2485 kg/m3
d
h
r
D
Measurement line
for velocities at
h/H=0.2
Comparison of vertical solid concentration
1
0.9
Experimental
0.8
STAR-CCM+
Star-CCM+
0.7
h/H
0.6
0.5
0.4
0.3
0.2
0.1
0
0
1
2
3
C/<C>
4
5
Comparison of liquid velocities
Liquid Velocities
0.5
0.3
Uz
Experimental
Uz
Star-CCM+
STAR-CCM+
0.2
Ur Experimental
0.4
U/Utip
0.1
Ur
Star-CCM+
STAR-CCM+
0
Utheta
Experimental
-0.1
STAR-CCM+
-0.2
-0.3
-0.4
-0.5
0
0.5
r/R
1
Comparison of solids velocities
Solids Velocities
0.5
0.4
Uz Experimental
0.3
STAR-CCM+
Uz
Star-CCM+
0.2
Ur Experimental
U/Utip
0.1
Ur
Star-CCM+
STAR-CCM+
0
-0.1
Utheta
Experimental
-0.2
STAR-CCM+
-0.3
-0.4
-0.5
0
0.5
r/R
1
Interphase transfer of chemical species in
STAR-CCM+ v7.02
Allow chemical species transfer between phases: gas dissolving into liquid,
gas release from liquid.
Aimed for chemical, process, oil & gas, water, food,...
Applications: bubble columns in chemical process, aeration tanks in water
treatment, gas release in oil & gas risers, aeration in bio-reactors,...
Oxygen transfer in aeration tank in water treatment
Volume fraction of air
Oxygen in air
Water
Air injector
Oxygen in water
Oxygen level at water surface and
exit
Granular flow model in STAR-CCM+ v7.04
Kinetic theory model for granular flows.
Particle-particle collisions represented by a granular temperature equation
derived from kinetic theory.
Suitable for dense particle flows such as fluidised beds.
Aimed for chemical, process, oil & gas, water, food, cement, mineral,
pharmaceutical, agricultural, ...
Applications: fluidised bed reactors, sand and slurry transports, solid
handling,...
Fluidised bed
Case boundary conditions
•
Bottom inlet (only Gas Phase):



•
Mass Fraction: [Gas Oil, Steam] = [0.81, 0.19]
Velocity: 15.05m/s
Temperature: 600K
Side inlet [Steam , Catalyst particle]:



Volume Fraction: [0.9045, 0.0955]
Velocity: 1.8625 m/s
Temperature: 900K
11
Reacting multiphase flows
V7.04 – Eddy breakup & DARS-CFD reaction models working with EMP
V7.06 – enabling more reaction models
FCC example:
Three reactions
Gas Oil
Gasoline
 Gas Oil -> Gasoline
 Gas Oil -> Coke
 Gas Oil -> Light Gases
Catalyst + Steam
Gas Oil + Steam
Gasoline,
light gases,
coke
Boiling model in v6.06
Aimed for the nuclear power industry.
Consider boiling steam/water flow.
Applications: nuclear reactors.
Wall heat transfer
Total wall heat flux is therefore made up by three components:
qT  qc  qq  qe
Convective Quenching
heating
qc
q q
Evaporation
qe
14
PSBT International benchmark Case 1
Victor Petrov (Michigan)
PSBT 5x5 bundle
Spacer
with
mixing
vanes
Spacer
without
mixing
vanes
Simple
spacer
All rods and spacers in bundle
are modelled
Boiling flow in PSBT 5x5 bundle
Boiling flow in PSBT 5x5 bundle
Boiling flow in PSBT 5x5 bundle
CHT-Boiling model in STAR-CCM+ v7.04
Boiling on wall
producing steam
vapour flow in
channel
Heat conducting
wall (temperature not
shown)
Flow
Solid temperature
(Uniform heat
source in solid)
Summary
We will continue to validate the Eulerian multiphase (EMP) model against
industrial applications
We will continue to develop new capabilities in STAR-CCM+
–
–
–
–
–
Chemical reaction model (v7.04)
More turbulence model options (v7.04)
Multi-particle phases granular model (v7.06)
Coupling with liquid film model (v7.06)
Non-Newtonian model (v7.06)
We will continue to improve user experience of the models
– Robustness of models
– Clear model description in user manual, tutorial examples