multiphase flow models in star-ccm+ - siemens flow models in star-ccm+ vof –multiphase flow in...
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Multiphase flow models in
STAR-CCM+
Simon Lo
Multiphase flow models in STAR-CCM+
VOF
– Multiphase flow in long pipe
– Severe slugging in riser
– Slug flow around pipe elbow
DEM
– Particle transport in pipes
EMP
– Slurry flow in pipes
– Gas-liquid stirred vessel
– Oxygen transfer in aeration tank
– Reacting flow in fluidised bed reactors
Oil and gas flow in 100m pipeline
Severe slugging in riser, Uni of Cranfield, UK
4 inch riser
55 m pipeline
10.5 m
Riser top
Riser base
Riser DP = Pbase - Ptop
50 100 150 200 250 300 3500
0.2
0.4
0.6
0.8
1
Flow time t, s
Ris
er
DP
, bar
Experiment
Star-CD-1
Star-CD-2
Dynamic forces on pipe elbow in slug flow
Mass flux, velocity and density
Pressure and temperature
Model the long pipe
using OLGA with slug
tracking
Model pipe elbow using STAR-CCM+
Pressure variation due to slug flow pass elbow
Gas volume fraction Pressure on the outer part
Note the passing of
liquid slug in “blue”.
Note the increase in pressure
as liquid slug passes.
Comparison
Coupling model Experiment
Slug frequency (Hz) 0.5 0.5
Slug velocity (m/s) slug front: 2.8 to 3.6
slug tail: 3.0 to 3.5 3.6
Peak force on bend (N) 44 to 54 40 to 60
Maximum force on bend (N) 54 60
DEM – particle transport in pipe
DEM - Pneumatic conveying of particles in pipe
Liquid velocity
Inlet Outlet Middle
Particle volume fraction
Slurry flow in horizontal pipe
Uniform volume fraction (vf)
and velocity (V) g
L=10m
V
1m
D
Measurement plane
Slurry flow in pipe
d=90 m, vf=0.19,
D=103mm, V=3 m/s
d=165 m, vf=0.189,
D=51.5mm, V=4.17 m/s
Uniform volume fraction (vf)
and velocity (V) g
L=10m
V
1m
D
Measurement plane
d=270 m, vf=0.2,
D=51.5mm V=5.4 m/s
d=165 m, vf=0.0918
D=51.5mm V=3.78 m/s
d=480 m, vf=0.203,
D=51.5mm V=3.41 m/s
d=165 m, vf=0.273,
D=495mm V=3.46 m/s
Pigging – Overset mesh for moving pig
Stratified gas-liquid flow Dispersed solid-liquid flow
Effects of increasing gas injection rate
U=0.0184 m/s
Gas superficial velocity:
U=0.0448 m/s U=0.0835 m/s U=0.1175 m/s U=0.201 m/s
Comparison of gas holdup
0 0.05 0.1 0.15 0.2 0.250
5
10
15
20
25
30
35
40
45
50
Experimental
Star-CCM+
Superficial velocity [m/s]
Gas h
old
up
[%
]
STAR-CCM+
Oxygen transfer in aeration tank in water treatment
Volume fraction of air Oxygen in air
Oxygen in water Oxygen level at water surface and
exit
Water
Air injector
Granular flow
Reacting multiphase flow
Inter- and intra-phase reactions.
Gas Oil Gasoline
Gas Oil + Steam
Catalyst + Steam Gasoline,
light gases,
coke
Multiphase flow models in STAR-CCM+
VOF
– Multiphase flow in long pipe
– Severe slugging in riser
– Slug flow around pipe elbow
DEM
– Particle transport in pipes
EMP
– Slurry flow in pipes
– Gas-liquid stirred vessel
– Oxygen transfer in aeration tank
– Reacting flow in fluidised bed reactors
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