temperature evolution in the spray zones: plant
TRANSCRIPT
ANNUAL REPORT 2008UIUC, August 6, 2008
Xiaoxu Zhou (MS Student)Brian G. Thomas
Department of Mechanical Science and Engineering
University of Illinois at Urbana-Champaign
Temperature evolution in the spray zones:
plant measurements and CON1D prediction
University of Illinois at Urbana-Champaign • Metals Processing Simulation Lab • Xiaoxu Zhou 2
Acknowledgements
• Continuous Casting Consortium Members (Baosteel, Corus, Goodrich, Labein, LWB Refractories, Mittal, Nucor, Postech, Steel Dynamics, Ansys Inc.)
• National Science Foundation– GOALI DMI 05-00453 (Online)
• Other graduate students, especially Huan Li and Bryan Petrus James.
University of Illinois at Urbana-Champaign • Metals Processing Simulation Lab • Xiaoxu Zhou 3
Outline
• Nucor trials-pyrometer measurements
• Con1d prediction of Nucor trials
• Con1d prediction of whale formation
• Con1d tests of hysteresis
• Conclusions
University of Illinois at Urbana-Champaign • Metals Processing Simulation Lab • Xiaoxu Zhou 4
Pyrometers location
Pyrometer 1
Pyrometer 2
Pyrometer 3
Pyrometer 4
Pyrometer 5
University of Illinois at Urbana-Champaign • Metals Processing Simulation Lab • Xiaoxu Zhou 5
Pyrometer Specifications
3866.1 mmLocation of Pyrometer 4 from meniscus
13970 mmLocation of Pyrometer 5 from meniscus
6015.3 mmLocation of Pyrometer 3 from meniscus
8380 mmLocation of Pyrometer 2 from meniscus
11385 mmLocation of Pyrometer 1 from meniscus
15.5 mmFocus spot size
1346 mmLength
Modline® 5, 5R-141000, 4M5#25579Model Name and Number
University of Illinois at Urbana-Champaign • Metals Processing Simulation Lab • Xiaoxu Zhou 6
Spray zones configuration in con1d input file
1 (49)
10 (39~48)
1 (38)
9 (29~37)
1 (28)
9 (19~27)
1 (18)
5 (13~17)
6 (7~12)
5 (2~6)
1 (1)
# of Rolls
0.11510995.8(11)
0.0958495.8(10)
0.0958260.0(9)
0.0956130.3(8)
0.0955903.6(7)
0.0803968.6(6)
0.0803773.6(5)
0.0702823.3(4)
0.0621767(3)
0.062940(2)
0.062850(1)
Roll Radius (m)Zone StartsZone No.
University of Illinois at Urbana-Champaign • Metals Processing Simulation Lab • Xiaoxu Zhou 7
SouthCaster
Jan. 13, 2006, 1610-1640 hrs.Time of Experiment
1547.777 oCPouring Temperature
C .247Mn 1.09S 0.0019Al 0.039Ca .0018Si .175P .014Cu .087N (leco).0076
Composition of Elements (%)
4 to 7Spray Pattern Number
142.1 ipm (3.61 m/min) (0.06 m/s)Casting Speed
ValueParameter
Case 4 13 Jan Transient (Low and High Spray)
Nucor experiment (from Amar’s ccc meeting 2006)
•The casting speed kept constant.•The spray pattern went like high-low-high-low-high.
University of Illinois at Urbana-Champaign • Metals Processing Simulation Lab • Xiaoxu Zhou 8
Experimental Temperature Profile
-Amar Behera’s Nucor report
University of Illinois at Urbana-Champaign • Metals Processing Simulation Lab • Xiaoxu Zhou 9
Del avan 19813-3 Qw=10. 4 L/mi n
0500
1000150020002500300035004000
-60 -40 -20 0 20 40 60
Del avan 19813- 3 Qw=10. 4 L/mi n
0
20
40
60
80
100
- 60 - 40 - 20 0 20 40 60
Delavan 19813-3Distance down caster (mm)
Wat
er fl
ux (
L/m
2 s)
Hea
t tra
n C
oeff
(W/m
2K)
Water flow used in nozzle experiment
Characterize using CON1D
Estimated heat flux profile based on Nozaki correlation
--from Vapalahti’s 2006 ccc meeting report:
“Delavan Nozzle Characterization at CINVESTAV”
University of Illinois at Urbana-Champaign • Metals Processing Simulation Lab • Xiaoxu Zhou 10
Del avan 19813-5 Qw=6. 9 L/mi n
0
500
1000
1500
2000
2500
-60 -40 -20 0 20 40 60
Del avan 19813- 5 Qw=6. 9 L/mi n
0
5
10
1520
25
30
35
- 60 - 40 - 20 0 20 40 60
Water flow used in nozzle experiment
Delavan 19813-5Distance down caster (mm)
Wat
er fl
ux (
L/m
2 s)
Hea
t tra
n C
oeff
(W/m
2K)
Estimated heat flux profile based on Nozaki correlation
--from Vapalahti’s 2006 ccc meeting report:
“Delavan Nozzle Characterization at CINVESTAV”
Characterize using CON1D
University of Illinois at Urbana-Champaign • Metals Processing Simulation Lab • Xiaoxu Zhou 11
Distance down caster (mm)
Wat
er fl
ux (
L/m
2 s)
Hea
t tra
n C
oeff
(W/m
2K)
Characterize using CON1D
Estimated heat flux profile based on Nozaki correlation
--from Vapalahti’s 2006 ccc meeting report:
“Delavan Nozzle Characterization at CINVESTAV”
Del avan 3. 5-90 Qw=8. 5 L/mi n
0
500
1000
1500
2000
2500
3000
3500
-60 -40 -20 0 20 40 60
Del avan 3. 5- 90 Qw=8. 5 L/mi n
0
10
20
30
40
50
60
- 60 - 40 - 20 0 20 40 60
Delavan 3.5-90
Water flow used in nozzle experiment
University of Illinois at Urbana-Champaign • Metals Processing Simulation Lab • Xiaoxu Zhou 12
Distance down caster (mm)
Wat
er fl
ux (
L/m
2 s)
Hea
t tra
n C
oeff
(W/m
2K)
Characterize using CON1D
Estimated heat flux profile based on Nozaki correlation
--from Vapalahti’s 2006 ccc meeting report:
“Delavan Nozzle Characterization at CINVESTAV”
Del avan 51474-1 Qw=39 L/mi n
010002000300040005000600070008000
-60 -40 -20 0 20 40 60
Del avan 51474- 1 Qw=39 L/mi n
0
50
100
150
200
250
300
- 60 - 40 - 20 0 20 40 60
Water flow used in nozzle experiment
Delavan 51474-1
University of Illinois at Urbana-Champaign • Metals Processing Simulation Lab • Xiaoxu Zhou 13
Distance down caster (mm)
Wat
er fl
ux (
L/m
2 s)
Hea
t tra
n C
oeff
(W/m
2K)
Characterize using CON1D
Estimated heat flux profile based on Nozaki correlation
--from Vapalahti’s 2006 ccc meeting report:
“Delavan Nozzle Characterization at CINVESTAV”
Del avan 51468-1 Qw=25 L/mi n
0
1000
2000
3000
4000
5000
6000
-60 -40 -20 0 20 40 60
Del avan 51468- 1 Qw=25 L/mi n
020406080
100120140160
- 60 - 40 - 20 0 20 40 60
Water flow used in nozzle experiment
Delavan 51468-1
University of Illinois at Urbana-Champaign • Metals Processing Simulation Lab • Xiaoxu Zhou 14
Distance down caster (mm)
Wat
er fl
ux (
L/m
2 s)
Hea
t tra
n C
oeff
(W/m
2K)
Characterize using CON1D
Estimated heat flux profile based on Nozaki correlation
--from Vapalahti’s 2006 ccc meeting report:
“Delavan Nozzle Characterization at CINVESTAV”
Del avan W19822 Qw=10. 8 L/mi n
0
500
1000
1500
2000
2500
3000
3500
-60 -40 -20 0 20 40 60
Del avan W19822 Qw=10. 8 L/mi n
0
10
20
3040
50
60
70
- 60 - 40 - 20 0 20 40 60
Water flow used in nozzle experiment
Delavan W19822
University of Illinois at Urbana-Champaign • Metals Processing Simulation Lab • Xiaoxu Zhou 15
Con1d prediction of Nucor trails
3.61
m/min
Casting speed
h profile
0.7values
Water flow rates
Solid fraction
Spray length
Model parameters
Specific input variables:
Low High
University of Illinois at Urbana-Champaign • Metals Processing Simulation Lab • Xiaoxu Zhou 16
Con1d predictions-- case 4_low spray
600
700
800
900
1000
1100
1200
1300
0 2000 4000 6000 8000 10000 12000 14000 16000
Sur
face
Tem
pera
ture
(¡ã
C)
Distance below meniscus (mm)
CON1D: Shell Surface Temperature
case4_low spray(Nucor)pyrometer #1pyrometer #2pyrometer #3pyrometer #4pyrometer #5
-Huan’s Nucor trial ppt
University of Illinois at Urbana-Champaign • Metals Processing Simulation Lab • Xiaoxu Zhou 17
600
700
800
900
1000
1100
1200
1300
0 2000 4000 6000 8000 10000 12000 14000 16000
Sur
face
Tem
pera
ture
(¡ã
C)
Distance below meniscus (mm)
CON1D: Shell Surface Temperature
case4_high spray(Nucor)pyrometer #1pyrometer #2pyrometer #3pyrometer #4pyrometer #5
Con1d predictions-- case 4_high spray
-Huan’s Nucor trial ppt
University of Illinois at Urbana-Champaign • Metals Processing Simulation Lab • Xiaoxu Zhou 18
Con1d predictions(steady state simulation)
University of Illinois at Urbana-Champaign • Metals Processing Simulation Lab • Xiaoxu Zhou 19
Cononline Prediction(transient simulation)
University of Illinois at Urbana-Champaign • Metals Processing Simulation Lab • Xiaoxu Zhou 20
Observations
• Compared to pyrometer measurements Con1d gives highertemperature prediction in the spray region except the pyrometer 2 in the case 4_low spray. In order to match pyrometer 2 measurement, the heat transfer coefficient should be increased appropriately around 6000 mm down the strand.
• Pyrometer focuses the thermal radiation onto the detector. However, there is much mist around strand which should decrease the power intensity collected by pyrometers. Then, it is the fact that pyrometer gives lower reading.
• Thus, Con1d temperature prediction matches reasonably pyrometer measurements in the spray region in these two cases.
University of Illinois at Urbana-Champaign • Metals Processing Simulation Lab • Xiaoxu Zhou 21
whale formation casesCasting conditions (Nucor Dec 9, 2003)
WhaleNo Whale No WhaleObservation at Plant
611Spray Pattern
146157146Casting Speed
(ipm)
Case 3Case 2Case 1
Containment limit = 11246.0mm
Flat-top for all sparys
( z1 z2 z3 h1 h2 h3 )
(0 0.5 1.0 1.0 1. 0 1.0)
0.70.05 mm for all sprays
values
h profileSolid fraction
Spray lengthModel parameters
Specific input variables in con1d:
University of Illinois at Urbana-Champaign • Metals Processing Simulation Lab • Xiaoxu Zhou 22
Con1d prediction of Case 1
0
5
10
15
20
25
30
35
40
45
0 2000 4000 6000 8000 10000 12000 14000600
700
800
900
1000
1100
1200
1300
1400
1500
Distance down meniscus,mm
Thi
ckne
ss, m
m
Tem
pera
ture
, Deg
C
Solidus Liquidus Shell surf TSolid
Note: no whale, matchthe observation
University of Illinois at Urbana-Champaign • Metals Processing Simulation Lab • Xiaoxu Zhou 23
Con1d prediction of Case 2
0
5
10
15
20
25
30
35
40
45
0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000 11000 12000 13000 14000 15000600
700
800
900
1000
1100
1200
1300
1400
1500
Distance down meniscus,mm
Thi
ckne
ss, m
m
Tem
pera
ture
, Deg
C
Solidus Liquidus Shell surf TSolid
Note: Solid coincidescontainment limit.
University of Illinois at Urbana-Champaign • Metals Processing Simulation Lab • Xiaoxu Zhou 24
Con1d prediction of Case 3
0
5
10
15
20
25
30
35
40
45
0 2000 4000 6000 8000 10000 12000 14000600
700
800
900
1000
1100
1200
1300
1400
1500
Distance down meniscus,mm
Thi
ckne
ss, m
m
Tem
pera
ture
, Deg
C
Solidus Liquidus Shell surf TSolid
Note: whale, matchthe observation
University of Illinois at Urbana-Champaign • Metals Processing Simulation Lab • Xiaoxu Zhou 25
Con1d prediction of whale formation of case 3 using pointed h profile
3.9878
m/min
(157ipm)
Casting speed
h profile
0.7values
Water flow rates
Solid fraction
Spray lengthModel paramet
ers
Input variables:
University of Illinois at Urbana-Champaign • Metals Processing Simulation Lab • Xiaoxu Zhou 26
Whale formation Con1d9.6 prediction Case3
Shel l gr owt h & Sur f t emp ( 146i pm Spr ay pat t er n_6)
600
700
800
900
1000
1100
1200
1300
1400
1500
1600
0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000 11000 12000 13000 14000 15000
di st ance bel ow meni scus ( mm)
Temp
(de
g c)
0
5
10
15
20
25
30
35
40
45
50
thic
knes
s (m
m)
Sur f Temp Li qui dus Sol i dus Shel l
Whale observed in the plantfor Case 3.
But prediction gives solid far away before containment limit.
Conclusions:Heat transfer coefficients were too high
Pyrometer temperatures (which are matched by this run) were reading too low
University of Illinois at Urbana-Champaign • Metals Processing Simulation Lab • Xiaoxu Zhou 27
Leidenfrost effect with hysteresis
1000
1.6
1050.900.800700.temperatures
1.02.21.21.0h-multipliers
•Con1d 9.6 was modified to consider hysteresis in Liedenfrosteffect:
•If surface temperature tsnext > ts, meaning heating, LF effect is employed.•If surface temperature tsnext<ts, meaning cooling, LF effect is not employed.
• Using the following set of h multipliers
University of Illinois at Urbana-Champaign • Metals Processing Simulation Lab • Xiaoxu Zhou 28
Hysteresis effect
600
700
800
900
1000
1100
1200
0 2000 4000 6000 8000 10000 12000 14000 16000
Distance below meniscus,mm
Sh
ell
su
rfa
ce
te
mp
era
ture
, De
g
C
LF effect always ON Hysteresis employed
University of Illinois at Urbana-Champaign • Metals Processing Simulation Lab • Xiaoxu Zhou 29
Hysteresis effect
600
700
800
900
1000
1100
1200
0 2000 4000 6000 8000 10000 12000 14000 16000
Distance below meniscus,mm
Sh
ell
su
rfa
ce
te
mp
era
ture
,De
g C
Hysteresis employed Hysteresis always OFF
University of Illinois at Urbana-Champaign • Metals Processing Simulation Lab • Xiaoxu Zhou 30
Conclusion and future work
• Several CON1D simulations have been combined to show that pyrometer measurements maybe not believable.
• Hysteresis based on heating / cooling is oversimplified, as fluctuations between rolls made the Leidenfrost effect with hysteresis negligible in test simulations.
• Parameters are needed to simultaneously match: – lab heat extraction measurements at Cinvestav– Pyrometer temperatures or TC traces measured at plant– Whale formation / shell thickness