ANNUAL REPORT 2006 Meeting date: June 15, 2006 Temperature evolution in the spray zones: Plant measurements and CON1D predictions Amar Kumar Behera (Ph.D. Student) & Brian G. Thomas Department of Mechanical & Industrial Engineering University of Illinois at Urbana-Champaign University of Illinois at Urbana-Champaign Metals Processing Simulation Lab AK Behera 1 Surface Temperature down strand 1400 34 68 103 137 171 205 240 257 (sec) time (s) Surface Temperature ( o C) Temperature (degree) 1300 1200 1100 1000 mold spray zone (rolls) Radiation zone 900 0 2000 4000 6000 8000 10000 12000 14000 16000 Distance from Meniscus (mm) Distance below Meniscus (mm) Example: thin slab caster 3.5 m/min Note: reheating below mold; and after sprays variations caused by rolls (slab caster) University of Illinois at Urbana-Champaign Metals Processing Simulation Lab AK Behera 2
Heat transfer between rolls natural/forced convection, hconv Slab Roll Spray nozzle radiation, hrad_spray spray impinging, hspray roll contact, hroll Distance (mm) 4000 3950 3900 3850 3800 3750 3700 950 1000 1050 1100 1150 1200 1250 heat transfer Surface Temperature ( 0 C) University of Illinois at Urbana-Champaign Metals Processing Simulation Lab AK Behera 3 Pyrometer Locations Pyrometer 1 Pyrometer 2 Pyrometer 3 Pyrometer 4 Pyrometer 5 University of Illinois at Urbana-Champaign Metals Processing Simulation Lab AK Behera 4
Pyrometer Specifications Model Name and Number Length Focus spot size Location of Pyrometer 1 from meniscus Location of Pyrometer 2 from meniscus Location of Pyrometer 3 from meniscus Location of Pyrometer 4 from meniscus Location of Pyrometer 5 from meniscus Modline 5, 5R-141000, 4M5#25579 1346 mm 15.5 mm 11385 mm 8380 mm 6015.3 mm 3875 mm 13970 mm University of Illinois at Urbana-Champaign Metals Processing Simulation Lab AK Behera 5 Zones in CON1D File Zone No. M/S (1) M/S, IA, IB (2) IB (3) IB, II (4) II, III (5) III (6) III, IV (7) IV (8) IV (9) V (10) V (11) ( ) CON1D Zone No. Zone Starts # of Rolls Roll Radius (m) 850 1 0.062 940 5 0.062 1767 6 0.062 2823.3 5 0.070 3773.6 1 0.080 3968.6 9 0.080 5903.6 1 0.095 6130.3 9 0.095 8260.0 1 0.095 8495.8 10 0.095 10995.8 1 0.115 11246.0 End of last spray zone (mm) University of Illinois at Urbana-Champaign Metals Processing Simulation Lab AK Behera 6
Experiments at Nucor Steel Case Number 1 2 3 4 Time 01/13/06-0950-1010 01/13/06-1535-1610 01/16/06-0945-1012 01/13/06 1610-1640 Steady/ Transient Steady Steady Steady Transient University of Illinois at Urbana-Champaign Metals Processing Simulation Lab AK Behera 7 Case 1 13 Jan Steady State Parameter Value Time of Experiment Casting Speed Spray Pattern Number Composition (%) Caster Pouring Temperature 0950-1010 hrs. 135.4 ipm (3.44 m/min) (0.057 m/s) 2 C 0.247% Mn 1.09 S 0.0019 Al 0.039 Ca.0018 Si.175 P.014 Cu.087 N (leco).0076 North 1542.222 o C University of Illinois at Urbana-Champaign Metals Processing Simulation Lab AK Behera 8
Simulation CON1D Mold Heat Flux Mean heat flux (MW/m 2 ) Powder Viscosity at 1300 o C (Pa-s) Melting Temperature of Mold Flux ( o C) Carbon Content Casting Speed (m/min) μ = 0.025 Pa-s 0 T 0 flow = 1180 C 7 Mold Heat Flux - Casting Speed 3.44 m/min, % Carbon 0.247 Average Mold Heat Flux - Argentina Paper Nucor Case 1 6 Average Mold Heat Flux - Experiment Nucor Case 1 MOLD HEAT FLUX (MW/m^2) 5 4 3 2 1 0 100 200 300 400 500 600 700 800 DISTANCE BELOW MENISCUS (mm) University of Illinois at Urbana-Champaign Metals Processing Simulation Lab AK Behera 9 Simulation CON1D Spray Zones h (W/m^2K) 4500 4000 3500 3000 2500 2000 1500 1000 500 Radiation heat transfer coefficient, h_rad Spray heat transfer coefficient, h_spray Roll heat transfer coefficient, h_roll 0 3700 3750 3800 3850 3900 3950 4000 4050 Distance below meniscus (mm) Water Flux Temperature of spray cooling water Ambient Temperature Fraction of heat extraction to rolls Nozaki - A=0.3925 c=0.55 b=0.0075 0 steel = 0.8 Tspray = Tamb = 25 C 8 σ = 5.67*10 WK ε 0 3700 3750 3800 3850 3900 3950 4000 4050 4 2 Distance below meniscus (mm) m University of Illinois at Urbana-Champaign Metals Processing Simulation Lab AK Behera 10 h (W/m^2K) 4500 4000 3500 3000 2500 2000 1500 1000 500 Total heat transfer coefficient, h_tot
Case 1 Results 1300 1200 Close up comparision Result Outer Surface Temperature - CONID Pyrometer Temperature Pyrometer Temperature Prediction -CON1D 4500 3750 Surface Temperature (C) 1100 1000 900 2 1 5 3000 2250 1500 h (W/m^2K) 800 4 3 750 700 0 2000 4000 6000 8000 10000 12000 14000 Distance below meniscus (mm) 0 University of Illinois at Urbana-Champaign Metals Processing Simulation Lab AK Behera 11 Pyrometer 4 Zone 4 Zone 5 Zone 6 Φ140 Φ160 University of Illinois at Urbana-Champaign Metals Processing Simulation Lab AK Behera 12
Pyrometer 3 Zone 6 Zone 7 Zone 8 Φ160 Φ190 University of Illinois at Urbana-Champaign Metals Processing Simulation Lab AK Behera 13 Pyrometer 2 Zone 8 Zone 9 Zone 10 Φ190 Φ190 University of Illinois at Urbana-Champaign Metals Processing Simulation Lab AK Behera 14
Pyrometer 1 Zone 10 Zone 11 Beyond zone 11 Φ190 Φ230 University of Illinois at Urbana-Champaign Metals Processing Simulation Lab AK Behera 15 Pyrometer 5 Beyond zone 11 University of Illinois at Urbana-Champaign Metals Processing Simulation Lab AK Behera 16
Case 2-13 Jan Steady State Time of Experiment Casting Speed Caster Parameter Spray Pattern Number Composition of Elements (%) Pouring Temperature 1535-1610 hrs. 142.1 ipm (3.61 m/min) (0.06 m/s) 4 C.247 Mn 1.09 S 0.0019 Al 0.039 Ca.0018 Si.175 P.014 Cu.087 N (leco).0076 South 1547.777 o C Value University of Illinois at Urbana-Champaign Metals Processing Simulation Lab AK Behera 17 Case 2 Results 1300 1200 Close up comparision Result Outer Surface Temperature - CONID Pyrometer Temperature Pyrometer Temperature Prediction -CON1D 4500 3750 Surface Temperature (C) 1100 1000 900 800 3000 2250 1500 750 h (W/m^2K) 700 0 2000 4000 6000 8000 10000 12000 14000 Distance below meniscus (mm) 0 University of Illinois at Urbana-Champaign Metals Processing Simulation Lab AK Behera 18
Pyrometer 4 Zone 4 Zone 5 Zone 6 Φ140 Φ160 University of Illinois at Urbana-Champaign Metals Processing Simulation Lab AK Behera 19 Pyrometer 3 Zone 6 Zone 7 Zone 8 Φ160 Φ190 University of Illinois at Urbana-Champaign Metals Processing Simulation Lab AK Behera 20
Pyrometer 2 Zone 8 Zone 9 Zone 10 Φ190 Φ190 University of Illinois at Urbana-Champaign Metals Processing Simulation Lab AK Behera 21 Pyrometer 1 Zone 10 Zone 11 Beyond zone 11 Φ190 Φ230 University of Illinois at Urbana-Champaign Metals Processing Simulation Lab AK Behera 22
Case 3 16 Jan Steady State Parameter Time of Experiment Casting Speed Spray Pattern Number Composition of Elements (%) Pouring Temperature 0945-1012 hrs. 118.1 ipm (3.03 m/min) (0.051 m/s) 1 C.247 Mn 1.09 S 0.0019 Al 0.039 Ca.0018 Si.175 P.014 Cu.087 N (leco).0076 1556.944 o C Value University of Illinois at Urbana-Champaign Metals Processing Simulation Lab AK Behera 23 Case 3 Results Surface Temperature (C) 1300 1200 1100 1000 900 800 Close up comparision Result Outer Surface Temperature - CONID Pyrometer Temperature Pyrometer Temperature Prediction -CON1D 4500 3750 3000 2250 1500 750 h (W/m^2K) 700 0 2000 4000 6000 8000 10000 12000 14000 Distance below meniscus (mm) 0 University of Illinois at Urbana-Champaign Metals Processing Simulation Lab AK Behera 24
Pyrometer 2 Zone 8 Zone 9 Zone 10 Φ190 Φ190 University of Illinois at Urbana-Champaign Metals Processing Simulation Lab AK Behera 25 Pyrometer 1 Zone 10 Zone 11 Beyond zone 11 Φ190 Φ230 University of Illinois at Urbana-Champaign Metals Processing Simulation Lab AK Behera 26
Case 4 13 Jan Transient Time of Experiment Casting Speed Caster Parameter Spray Pattern Number Composition of Elements (%) Pouring Temperature 1610-1640 hrs. 142.1 ipm (3.61 m/min) (0.06 m/s) 4 to 7 C.247 Mn 1.09 S 0.0019 Al 0.039 Ca.0018 Si.175 P.014 Cu.087 N (leco).0076 South 1547.777 o C Value University of Illinois at Urbana-Champaign Metals Processing Simulation Lab AK Behera 27 Spray Pattern Change University of Illinois at Urbana-Champaign Metals Processing Simulation Lab AK Behera 28
Spray Pattern Change University of Illinois at Urbana-Champaign Metals Processing Simulation Lab AK Behera 29 Spray Pattern Change University of Illinois at Urbana-Champaign Metals Processing Simulation Lab AK Behera 30
Experimental Temperature Profile University of Illinois at Urbana-Champaign Metals Processing Simulation Lab AK Behera 31 Case 4 Pyrometer 4 3875 mm University of Illinois at Urbana-Champaign Metals Processing Simulation Lab AK Behera 32
Case 4 Pyrometer 3 6015.3 mm University of Illinois at Urbana-Champaign Metals Processing Simulation Lab AK Behera 33 Case 4 Pyrometer 2 8380 mm University of Illinois at Urbana-Champaign Metals Processing Simulation Lab AK Behera 34
Case 4 Pyrometer 1 11385 mm University of Illinois at Urbana-Champaign Metals Processing Simulation Lab AK Behera 35 Case 4 Results Pyrometer 5 13970 mm University of Illinois at Urbana-Champaign Metals Processing Simulation Lab AK Behera 36
Sources of Error Steam surrounding the slab Scale formation Pyrometer positioning Random Noise in PDA system University of Illinois at Urbana-Champaign Metals Processing Simulation Lab AK Behera 37 Conclusions Comparison of Temperature Profile from CON1D with Pyrometer Measurements shows good results for pyrometers 5,1 and 2 Pyrometers at top of caster (3 and 4) are consistently over-predicted Transient behavior seems to be modeled reasonably University of Illinois at Urbana-Champaign Metals Processing Simulation Lab AK Behera 38
Future Work Further calibration of CON1D S. Vapalahti experiments in Mexico Top hat Heat transfer profile to be put in place of Flat top Transient case with casting speed variation to be studied University of Illinois at Urbana-Champaign Metals Processing Simulation Lab AK Behera 39