Effects of Clogging, Argon Injection and Casting Conditions on Flow

Effects of Clogging, Argon Injection and Casting Conditions

on Flow Rate and Air Aspiration in Submerged Entry Nozzles

Hua Bai and Brian G. Thomas

Continuous Casting Consortium University of Illinois at Urbana-Champaign


� Continuous Casting Consortium (CCC)Allegheny Ludlum, (Brackenridge, PA) Armco Inc. (Middletown, OH),

Columbus Stainless (South Africa) Inland Steel Corp. (East Chicago, IN),

LTV Steel (Cleveland, OH) Stollberg, Inc., (Niagara Falls, NY)

� National Science Foundation (Grant #: DMI-98-00274) � Inland Steel, LTV Steel -- Casting Data� The National Center for Supercomputing Applications -- CPU time� AEA technology -- CFX4.2

Acknowledgments


Outline

� Introduction� Modeling multiphase flow of liquid steel-

argon bubbles in slide-gate nozzles� Development of the model describing

interrelated effects of casting conditions, clogging and argon injection

� Effects of clogging (initial and severe)� Effects on air aspiration (minimum pressure)� Conclusion


Introduction

� Argon injection into the nozzle is an efficient and widely employed method to reduce nozzle clogging

� Both clogging and argon injection greatly affect flow pattern in nozzle and mold

� Tundish nozzle geometry is one of the few variables that is both very influential on the continuous casting process and relatively inexpensive to change

� Casting operation variables are interrelated


Schematic of Continuous Casting Tundish, Nozzle, and Mold

Submerged Entry Nozzle (SEN)

Meniscus

Copper Mold

AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA

Slide Gate(flow control)

Submergence Depth

Liquid Steel Pool

Liquid Mold Flux

Solidifying Steel Shell

AAA

AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA

Continuous Withdrawal

Port Thickness

Port HeightPort Angle

Nozzle Bore

Upper Tundish Nozzle (UTN)

Molten Steel Jet

AAAAAAAAAAA

AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA

Tundish

AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA

AAAAAAAAAAAAAAAAAAAAAA

Liquid Steel

Protective Slag Layer

AAAAAAAAAAARefractory Brick Steel Tundish Wall

AAAA

AAAA

AAAAAA

Solid Mold Powder

AAAA

AAAAAAAA

AAA

AAA

Argon Gas Injection


Computational Domain and Boundary Conditions

Liquid Inlet from tundishnormal liquid velocity = constantK=constantε =constantLiquid volume fraction =1

Gas Injectionnormal gas velocity = constantArgon volume fraction =1

Outlets (both ports)pressure = constantzero normal gradients for velocities, K and ε

Tundish Well (Nozzle Top)

UTN(Upper Tundish Nozzle)

Slide-Gate Opening

SEN(Submerged Entry Nozzle)

Nozzle Ports

Shrould Holder


Simulation Conditions

Variable Value Notes

Casting Speed VC

(m/min)

0.2, 0.5, 1, 1.5, 2.0, 2.3 For 8”x52”

slab

Gate Opening FL

(%)

40, 50, 60, 70, 100 Linear opening

Argon Flow Rate QG

(SPLM)

0, 5, 10 “cold” argon

Nozzle Bore Diameter

DB (mm)

60, 70, 78, 90 Also simulates

clogging


Definitions of Slide-Gate Opening and Their Conversions

T

SL

D

Ref

eren

ce li

ne

Slide-gate plate Bore

AAAAAAAAAAAA

0

20

40

60

80

100

0 20 40 60 80 100

Slid

e-ga

te o

peni

ng (%

)

Slide-gate opening-linear fraction FL (%)

FP (M=41.7%)

FP (M=24%)

FL

FA

FL =LD

FP =ST

FA =Shadow Area

Bore Area

FP = (1− M)FL + M M =T − D

T

FA =2π

cos−1 1 − FL( )−2π

1 − FL( ) 1 − 1− FL( )2


Liquid Steel-Argon BubbleMultiphase Flow Model

� “Multi-fluid” Eulerian multiphase model» one solution field for each phase

� Coupling achieved through inter-phase drag between liquid and gas bubbles.

� K-ε model for turbulence� Validated with velocity measurements using

PIV on a 0.4 scale water model and reported on» H. Bai and B.G. Thomas, "Two Phase Flow in Tundish Nozzles During

Continuous Casting of Steel" (Paper presented at Materials Processing in the Computer Age III, TMS Annual Meeting, Nashville, TN, 2000).


Argon Distribution in Nozzle

1.0000E-061.6667E-013.3333E-015.0000E-016.6667E-018.3333E-011.0000E+00

Volume fraction of liquid steel


Flow Pattern in Nozzle

Fe


Pressure Distribution in Nozzle

0 20 40 60 80 100

0

200

400

600

800

1000

FL=40%, HT=1.545m

FL=50%, HT=0.904m

FL=60%, HT=0.653m

FL=70%, HT=0.583m

FL=100%, HT=0.513m

(b) Pressure (KPa)

Dis

tanc

e fr

om th

e po

int O

at t

he c

ente

r lin

e (m

m)

Argon injection QG=10 SLPMCasting speed VC=1m/minNozzle bore diameter DB=78mm

Gate opening FL Tundish level HT

FL=40%

50%60%FL=100%

FL=70%

z

x

o

HighPressure

LowPressure

(a)

z

xo


Bernoulli’s Equation

TundishH

A

B

C

D

Hsubm

∆P = PB - PC

(1) Apply Bernoulli’s Equation on A and B:

Or

(2) Nozzle pressure drop ∆P = PB - PC

(3) Apply Bernoulli’s Equation on C and D:

Or

Combining (1),(2) and (3) gives

0 + 0 + ρgHT = PB + 12 ρU B

2 + 0

PA + 12 ρUA

2 + ρgZA = PB + 12 ρUB

2 + ρgZB

HT =PB + 1

2 ρUB2

ρg

PC + 12 ρUC

2 + ρgZC = PD + 12 ρUD

2 + ρgZD

PC + 12 ρUC

2 +0 = 0 + 0 + ρgHsubm

PC = ρgHsubm − 12 ρUC

2

HT =∆P + ρgHsubm + 1

2 ρ(UB2 − UC

2 )ρg

zT

Mold

Tundish Bath Depth


Multivariable Curve Fitting for Tundish Bath Depth

0

0.5

1

1.5

2

0 0.5 1 1.5 2 2.5

Tund

ish

bath

dep

th H

T (m)

Casting speed VC

(m/min, for 8"x52" slab)

Argon injection QG=10 SLPM

FL=10%

20%30%

40%50%

60% 70% 80%90%

100%

Gate opening FL

Nozzle bore diameter DB=78mm

0

0.5

1

1.5

2

2.5

3

0 5 10 15

Tund

ish

bath

dep

th H

T (m)

Argon injection flow rate: QG(SLPM)

Gate opening FL=50%

casting speed Vc (m/min, for 8"x52" slab)

Vc=2.3

Vc=2.0

Vc=1.5

Vc=1.0

Vc=0.5

Vc=0.2 Nozzle bore diameter DB=78mm

0

0.5

1

1.5

2

2.5

3

3.5

4

60 65 70 75 80 85 90

Tund

ish

bath

dep

th H

T (m)

Nozzle bore diameter DB (mm)

FL=40%

50%

60%70%

100%

Casting speed VC=1m/min for 8"x52" slab

Argon injection QG=10SLPM

Gate opening FL

0

0.5

1

1.5

2

0 20 40 60 80 100

Tund

ish

bath

dep

th H

T (m)

Gate opening FL(%)

Casting speed Vc (m/min, for 8"x52" slab)

Vc=2.5Vc=2.3

Vc=2.0

Vc=1.5

Vc=0.5

Vc=1.0

Vc=0.2



HT vs. VC

HT vs. FL

HT vs. QG

HT vs. DB

HT Tundish bath depth

VCCasting speed

FLGate opening

QGArgon flow rate

DBNozzle bore dia.


Multivariable Curve Fitting Model for Tundish Bath Depth

FL ≤ 60%

FL ≥ 60%

@

@HT -- Tundish bath depth, VC -- Casting speed, FL -- Gate opening , QG -- Argon flow rate, DB -- Nozzle bore diameter

HT = a1VC2 + a2VC + a3( ) a4 FL

2 + a5FL + a6( )a7QG + a8( ) a9 DB

3 + a10 DB2 + a11DB + a12( )

HT = a13VC2 + a14VC + a15( ) a16FL + a17( )

a18QG + a19( ) a20DB3 + a21DB

2 + a22DB + a23( )


Effect of Argon Injection on Casting Speed

0

0.5

1

1.5

2

0

0.1

0.2

0.3

0.4

0.5

0 2 4 6 8 10

Cas

ting

spee

d V

C (m

/min

, for

8"x

52"

slab

)Steel flow

rate (m3/m

in)


HT=1.6m

HT=1.4m

HT=1.2m

HT=1.0m

HT=0.8m

HT=0.6m

HT=0.4m

HT=0.2m

Tundish bath depth: HT

Gate opening FL=50%



Casting Speed, Gate Opening and Tundish Bath Depth Relation

0

1

2

3

4

5

0

0.2

0.4

0.6

0.8

1

1.2

0 20 40 60 80 100

Gate opening : Area fraction FA(%)

Cas

ting

spee

d V

C(m

/min

, 8"x

52"

slab

)

Steel flow rate (m

3/min)

Gate opening : Linear fraction FL(%)

0 20 40 60 80 100

Argon injection: QG=10 SLPM



HT=1.6m

HT=1.4m

HT=1.2m

HT=1.0m

HT=0.8m

HT=0.6m


Casting Speed, Gate Opening and Tundish Bath Depth Relation

0

1

2

3

4

5

0

0.2

0.4

0.6

0.8

1

1.2

0 20 40 60 80 100

Gate opening : Area fraction FA(%)

Cas

ting

spee

d V

C(m

/min

, 8"x

52"

slab

)

Steel flow rate (m

3/min)

Gate opening : Linear fraction FL(%)


Argon injection: QG=5 SLPM


HT=1.6m

HT=1.4m

HT=1.2m

HT=1.0m

HT=0.8m

HT=0.6m H

T=0.4m

0 20 40 60 80 100


Comparison of Model Predictions with Plant Measurements

0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.50.0

10

20

30

40

50

60

70

80

0

Model prediction(standard nozzle)

CFX simulation (actual nozzle)

Measured data fitting curve

Measured dataA ~ Z

Steel throughput (tonne/min)

Slid

e-g

ate

op

enin

g F

p (

%, p

lan

t d

efin

itio

n) Measured data legend: A = 1 obs, B = 2 obs, etc.

All data for the first heat

AAAAAAAAAAAAAA

AAAAAAAAAAAA

AAAAAAAAAAAAAAAAAAAAAAA

AAAAAAAAA

AA

Slid

e-g

ate

op

enin

g F

L (

%)

0

10

20

30

40

50

60

70

0.0 0.25 0.50 0.75 1.00 1.25 1.50 1.75 2.00 2.25

Casting speed VC (m/min, for 8”x52” slab)


Schematic of Initial Clogging and Rounded Edges in Vicinity of the Slide-Gate

AAAA

AAAAAAA

AAAAAAAA

AAAA

AAAAAA AA

AAAA

(a) Sharp edges (b) Rounded edges (c) Sharp edges with (d)Sharp edges with initial clogging more inital clogging


Effects of Initial Clogging and Rounded Edges

0

0.2

0.4

0.6

0.8

1

1.2

1.4

0.927m

1.340m

1.102m1.015m

0.856m

Tund

ish

bath

dep

th (

m)

Prediction

Sharp edges

Roundedges

Sharp edgeswith initial clogging

Sharp edgeswith moreinitial clogging

Measurement(a) (b) (c) (d)


Effects of Initial Clogging and Rounded Edges on Flow Pattern

Sharp edge Round edge Initial clogging More initial(a) (b) (c) (d)

clogging


Effects of Clogging or Nozzle Bore Size

0

20

40

60

80

100

50 60 70 80 90 100

Gat

e op

enin

g F

L (%

)

Nozzle bore diameter DB(mm)

HT=0.6m

HT=0.8m

HT=1.0m

HT=1.2m

HT=1.4m

HT=1.6m





Effects of Clogging or Nozzle Bore Size

0

0.5

1

1.5

2

2.5

50 60 70 80 90 100

Cas

ting

spee

d V

C (m

/min

, 8"x

52"s

lab)


HT=0.6mH

T=0.8m

HT=1.0m

HT=1.2m

HT=1.4m

HT=1.6m


Gate opening FL=50%



Curve Fitting for Minimum Pressure in Nozzle

-100

-80

-60

-40

-20

0

20

0 0.5 1 1.5 2 2.5

Low

est p

ress

ure

in n

ozzl

e P

L (k

Pa)

Casting speed VC


40%

50%

60%

70%

FL=100%


Gate opening FL


-100

-80

-60

-40

-20

0

20

0 2 4 6 8 10

Low

est p

ress

ure

in n

ozzl

e P

L (k

Pa)


Vc=0.2Vc=0.5

Vc=1.0

Vc=1.5

Vc=2.0

Vc=2.3casting speed Vc


Gate opening FL=50%


-50

-40

-30

-20

-10

0

10

20

60 65 70 75 80 85 90

Low

est P

ress

ure

in N

ozzl

e P

L(k

Pa)




Gate opening FL

100%

70%60%

50%

FL=40%

-100

-80

-60

-40

-20

0

20

30 40 50 60 70 80 90 100

Low

est p

ress

ure

in n

ozzl

e P

L (k

Pa)

Gate 0pening FL(%)

Vc=0.2Vc=0.5

Vc=1.0

Vc=1.5

Vc=2.0

Vc=2.3

Vc=2.5

Casting speed Vc (m/min, for 8"x52" slab)



PL vs.VC PL vs.QG

PL vs.DB PL vs.FL

PL Minimum pressurein nozzle

VCCasting speed

FLGate opening

QGArgon flow rate

DBNozzle bore dia.


Multivariable Curve Fitting Model for Minimum Pressure in Nozzle

PL = b1VC2 + b2VC + b3( ) b4FL + b5( )

b6QG + b7( ) b8 DB3 + b9 DB

2 + b10DB + b11( )

PL = b12VC2 + b13VC + b14( ) b15FL + b16( )

b17QG + b18( ) b19DB3 + b20 DB

2 + b21DB + b22( )

FL ≤ 70%

FL ≥ 70%

@

@PL -- Minimum pressure in nozzle, VC -- Casting speed, FL -- Gate opening , QG -- Argon flow rate, DB -- Nozzle bore diameter


Effects of Casting Conditions on Air Aspiration

Low

est p

ress

ure

in n

ozzl

e P

L(kP

a)

Casting speed (Vc) and argon injection volume fraction (fg)

Vc(m/min) 8"x52"slab

1020

10203040

30

fg(%,hot)

fg(%,cold)

10090807060504030

20 90807060504030

20 90807060504030

20 807060504030

20 706050403010

20 6050403010

-60

-50

-40

-30

-20

-10

0

10

20

0 0.5 1 1.5 2 2.5

HT=0.6m

HT=0.8m

HT=1.0m

HT=1.2m

HT=1.4m

HT=1.6m

Argon injection flow rate QG=10SLPM



Gate opening FL(%)

@HT=0.6m

@HT=0.8m

@HT=1.0m@HT=1.2m

@HT=1.4m@HT=1.6m


Effect of Argon Injection on Air Aspiration in Nozzle

1020

102030

100807060504030

908070605040

2010 807060504030

30 7060504010

20 6050403010

20 50403010

90

3020

20

60

-80

-60

-40

-20

0

20

0 0.5 1 1.5 2 2.5

Low

est p

ress

ure

in n

ozzl

e P

L(kP

a)


fg(%,hot)

fg(%,cold)

Vc(m/min) 8"x52"slab




HT=0.6m

HT=0.8m

HT=1.0m

HT=1.2m

HT=1.4m

HT=1.6m

Gate opening FL(%)

@HT=0.6m

@HT=0.8m

@HT=1.0m@HT=1.2m

@HT=1.4m@HT=1.6m



0 0.5 1 1.5 2 2.5-50

-40

-30

-20

-10

0

10

1020

10203040

100807060504030

908070605040

20 807060504030

30 70605040

20 6050403010

20 50403010

90

3020

20

60

100

90

80

70 80

70Lo

wes

t pre

ssur

e in

noz

zle

PL(

kPa)


Vc(m/min) 8"x52"slabfg(%,hot)

fg(%,cold)




HT=0.6m

HT=0.8m

HT=1.0m

HT=1.2m

HT=1.4m

HT=1.6m

Gate opening FL(%)

@HT=0.6m

@HT=0.8m

@HT=1.0m@HT=1.2m

@HT=1.4m@HT=1.6m



Argon injection flow rate (QG) and volume fraction (fg)

QG(SLPM)

1 2

102 4 6

58 706052 54 56

5048

44 4846

444240

424038

3634

52

38

8 12 14

3

-15

-10

-5

0

5

10

15

0 2 4 6 8 10

Casting speed Vc =1m/min



Low

est p

ress

ure

in n

ozzl

e P

L(kP

a)

fg(%,hot)

fg(%,cold)

HT=0.6m

HT=0.8m

HT=1.0mHT=1.2m

HT=1.4m

HT=1.6m

Gate opening FL(%)

@HT=0.6m

@HT=0.8m

@HT=1.0m@HT=1.2m

@HT=1.4m@HT=1.6m



64

1 2

102 4 6

85 959070 75 80

6257

54 5655

535250

504948

4746 48

8

Tundish bath depth: HTHT=0.6m

HT=0.8m

HT=1.0mHT=1.2mHT=1.4m

HT=1.6m

-40

-30

-20

-10

0

10

20

0 2 4 6 8 10

51

53

58 59 60 66 68 70

Casting speed Vc =1.5 m/minNozzle bore diameter DB=78mm

Argon injection flow rate (QG) and volume fraction (fg)

QG(SLPM)

Low

est p

ress

ure

in n

ozzl

e P

L(kP

a)

fg(%,hot)

fg(%,cold)

Gate opening FL(%)

@HT=0.6m

@HT=0.8m

@HT=1.0m@HT=1.2m

@HT=1.4m@HT=1.6m


Minimum Argon Flow Rate Required to Eliminate Air Aspiration in Nozzle

0

20

40

60

80

100

0 0.5 1 1.5 2 2.5

HT=0.6m

HT=0.8m

HT=1.0m

HT=1.2m

HT=1.4m

HT=1.6m

Cor

resp

ondi

ng g

ate

open

ing

FL (%

)



0

5

10

15

20

25

30

35

40

0 0.5 1 1.5 2 2.5

Min

imum

arg

on fl

ow ra

te (S

LPM

) req

uire

d fo

r pos

itive

low

est p

ress

ure

in n

ozzl

e

Casting speed VC


HT=0.6m

HT=0.8m

HT=1.0m

HT=1.2m

HT=1.4m

HT=1.6mNozzle bore diameter D

B=78mm



Minimum Argon Flow Rate Required to Eliminate Air Aspiration in Nozzle

0

20

40

60

80

100

0 0.5 1 1.5 2 2.5

HT=0.6m

HT=0.8m

HT=1.0m

HT=1.2m

HT=1.4m

HT=1.6m

V



Cor

resp

ondi

ng g

ate

open

ing

FL (%

)

0

5

10

15

20

25

30

0 0.5 1 1.5 2 2.5

Casting speed VC


HT=0.6m

HT=0.8m

HT=1.0m

HT=1.2m

HT=1.4m

HT=1.6mNozzle bore diameter D

B=70mm


Min

imum

arg

on fl

ow ra

te (S

LPM

) req

uire

d fo

r pos

itive

low

est p

ress

ure

in n

ozzl

e


Observations

� Clogging» The clogging condition (Clogging Index) can be detected by

comparing the measured steel flow rate to the theoretical value.» Initial clogging may enhance the flow due to a potential streamlining

effect before it becomes great enough to restrict the flow channel.

� Argon Injection» Increasing argon injection may help to reduce air aspiration by

increasing the minimum pressure below the slide gate. » More argon is needed at intermediate casting speeds and in deeper

tundishes. » Less argon is needed during shallow tundish and low casting speed

conditions in order to avoid detrimental effects on flow pattern. » Less argon is needed at high casting speed, when the slide gate is

open wider and the potential for air aspiration is less. » The optimal argon flow rate depends on the casting speed, tundish

level, nozzle bore diameter, and its influence on flow pattern in mold


Observations

� A small change in bath depth causes a larger change in casting speed at low casting speed than it does at high casting speed

� To maintain a constant low casting speed, a larger change in gate opening is needed to compensate for small changes in bath depth than maintaining a constant high casting speed

� For a fixed tundish bath depth, increasing argon injection will slightly slow down the casting speed unless the gate opening increases to compensate

� For a fixed tundish bath depth, casting speed is the most sensitive to gate opening changes at very large openings (FL>90%) and in the intermediate range of gate opening (FL=40%~60%).

Operation Variables’ Relation


Effects of Port Shape

0

5

10

15

20

25

30

78x78 64x95 50x122

Verti

cal j

et a

ngle

(°)

0

0.5

1

1.5

2

2.5

3

78x78 64x95 50x122

Hor

izon

tal j

et a

ngle

(°)

0

0.2

0.4

0.6

0.8

1

78x78 64x95 50x122

Jet s

peed

(m/s

)

0

5

10

15

78x78 64x95 50x122

Back

flow

zon

e fra

ctio

n (%

)

Vertical jet angle Horizontal jet angle

Jet speed Back flow zone ratio


Effect of Port Angle

-20

-10

0

10

20

30

-10

-5

0

5

10

-15 -10 -5 0 5 10 15 20 25

Verti

cal j

et a

ngle

(°, d

ownw

ard>

0)

Horizontal jet angle (°)

Nozzle Port Angle (°, down)

Vertical jet angle

Horizontal jet angle

0

5

10

15

20

0

0.1

0.2

0.3

0.4

0.5

-15 -10 -5 0 5 10 15 20 25Ba

ck fl

ow z

one

fract

ion

(%)

Average turbulence energy K (m3/s

2)

Nozzle Port Angle (°, down)

Back flow zone ratio (%)

Average turbulence energy (K)


Effect of Bubble Size

-5

0

5

10

15

20

0

5

10

15

20

0 0.05 0.1 0.15 0.2 0.25 0.3

D=1mmD=3mmD=5mm

D=1mmD=3mmD=5mm

Verti

cal j

et a

ngle

(°)


Vertical Jet Angle Horizontal Jet Angle

D: Bubble diameter

0 5 10 15 20

Argon injection flow rate (SLPM)

Gas injection volume fraction (fg)

0

5

10

15

20

25

30

0

0.1

0.2

0.3

0.4

0.5

0 0.05 0.1 0.15 0.2 0.25 0.3

D=1mmD=3mmD=5mm

D=1mmD=3mmD=5mm

Back

flow

zon

e fra

ctio

n (%

)

Average turbulence energy K (M3/s

2)

Argon gas volume fraction (%)

D: Bubble diameter

Back flow zone ratio (%) Ave turbulence K

0 5 10 15 20

Argon injection flow rate (SLPM)


Effect of Gate Opening

0

2

4

6

8

10

12

0

2

4

6

8

10

12

40 50 60 70 80 90 100

Verti

cal j

et a

ngle

(°, d

ownw

ard)


Slide gate opening FL (%)

Gate orientation: 90°Casting speed: Vc=1 m/minGas injection rate: Q

G=10SLPM

Vertical jet angle

Horizontal jet angle

0

0.2

0.4

0.6

0.8

1

0

5

10

15

20

40 50 60 70 80 90 100

Jet s

peed

(m/s

)

Back flow zone fraction (%

)

Back flow zone fraction

Jet speed


G=10SLPM


0

0.1

0.2

0

0.5

1

1.5

40 50 60 70 80 90 100

Turb

ulen

ce e

nerg

y (m

^2/s

^2)

Turbulence dissipation (m^2/s^3)

Turbulence energy



G=10SLPM

Turbulence dissipation


Two Jets on Each Port

Jet d

ivis

ion

line

Jet d

ivis

ion

line

z,w

y,vz,w

y,v

z,wy,v x,u

Back flow zone

Upward jet

Downward jet

Left port view Right port view


Comparing One Overall Jet with Two Separate Jets

Left Port Right PortJet mode Two-jets One-jet Two-jets One-jet

Jet Upwardjet

Downwardjet

Overallone-jet

Upwardjet

Downwardjet

Overallone-jet

Vertical jet angle 21.65°upward

8.30°downward

4.55°downward

20.59°upward

7.86°downward

2.41°downward

Jet speed (m/s) 0.56 0.81 0.76 0.67 0.87 0.81

Horizontal jetangle *

-4.70° 1.86° 1.06 -1.43 2.89 2.09

Back flow zonefraction

8.3% 20.1%

Area fraction ofport occupied

by jet

34.0% 57.7% 91.7% 31.3% 48.6% 79.9%

Liquid flowfraction carried

by jet

8.7% 48.1% 56.8% 9.2% 34.0% 43.2%

Jet gas fraction 61.5% 10.9% 25.8% 61.3% 11.7% 30.7%

Gas flow fractioncarried by jet

35.8% 15.1% 50.9% 37.5% 11.6% 49.1%

Documents

Effects of Clogging, Argon Injection and Casting Conditions on Flow