Multiphase flow models in STAR-CCM+mdx2.plm.automation.siemens.com/sites/default/files...Multiphase...

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