宽厚板坯结晶器流场温度场研究
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摘要
在连铸过程中,对铸坯质量影响最大的部件就是结晶器,它素有“连铸机心脏”之称。国内外学者对结晶器内流场和温度场的研究一直比较关注。但多数的研究都是在不考虑凝固坯壳存在的情况下,对流场与温度场进行耦合求解,或是直接对流场与温度场进行非耦合求解。本文采用商用软件FLUENT中的凝固融化模块与二次开发相结合的方法,选择SIMPLE算法,较好地模拟出凝固坯壳和两相区对结晶器内流场温度场的影响。
针对首秦公司的宽厚板坯连铸建立了结晶器内钢液流动、传热凝固的三维数学模型,计算得到了结晶器内钢液流场和温度场的分布规律。模型中将两相区处理为多孔介质,控制体的孔隙率和速度通过液相率来确定,并对凝固坯壳赋以拉坯速度,分析了凝固坯壳和糊状区对结晶器内钢液流场和温度场的影响。在考虑钢液凝固和糊状区孔隙率时,钢液的流动区域变小,钢液下回流区的涡心上移,其湍流特性明显增强。受下回流区涡流变化的影响,水口附近的液面波动也增大,同时流场的改变引起温度场的变化。因此,在进行结晶器流场温度场模拟时,必须考虑钢液的凝固,否则将影响计算结果。
此外,本文还模拟分析了浸入式水口出口倾角、水口壁厚、水口出口面积比、浸入深度、拉坯速度、过热度对宽厚板坯结晶器内钢液流动方式、传热和凝固的影响。通过分析不同工况下的结晶器内温度场和凝固壳厚度分布情况,合理设计水口的结构参数和操作工艺,提高拉坯速度和铸坯质量,指导连铸生产。
As the heart of slab conticaster, mould is the most important part of it. Many scholars, at home and abroad, pay more attention to the fluid flow and temperature distribution in slab continuous casting mold. But most of them simulate the process without regard to the influence of shell thickness and mushy zone. Or deal the heat transfer and the flow with segregated solver, The modeling solidification and melting of commercial FLUENT package and program designed is apply in this paper. The SIMPLE algorithm namely the Semi-Implicit Method for Pressure Linked Equations is employed to solve the equations. The flounce, because of the existence of shell thickness and mush zone, can be analyzed exactly.
Based on the mould of continuous casting for manufacture of steel slab that made in Qinhuangdao Shouqin metallic material Co., Ltd., the flow and temperature fields are simulated. The mushy zone is treated as a“pseudo”porous medium with porosity equal to the liquid fraction, and velocity is attention to it too. Shell thickness’velocity is equal to pull velocity. Because of shell thickness and mush zone, the flow zone is smaller and vortex center is rising, and the characteristic of flow field is evidence. Compared the change above, the fluctuation on top is larger, where near the SEN. And the temperature filed also change. The fluid solidification should be considered when we solve fluid flow problems. Or it must be wrong.
Furthermore, the research analyze the effect of outlet angle of SEN, thickness of SEN, the ratio of SEN’s outlet area to inlet, immersion depth of SEN, casting speed, superheat to flow field, temperature field and solidification in this thesis. Therefore, that simulating temperature distribution and shell thickness in mold under different working condition and design rational SEN and casting technology parameters will have useful guiding significance to the process of continuous casting.
针对首秦公司的宽厚板坯连铸建立了结晶器内钢液流动、传热凝固的三维数学模型,计算得到了结晶器内钢液流场和温度场的分布规律。模型中将两相区处理为多孔介质,控制体的孔隙率和速度通过液相率来确定,并对凝固坯壳赋以拉坯速度,分析了凝固坯壳和糊状区对结晶器内钢液流场和温度场的影响。在考虑钢液凝固和糊状区孔隙率时,钢液的流动区域变小,钢液下回流区的涡心上移,其湍流特性明显增强。受下回流区涡流变化的影响,水口附近的液面波动也增大,同时流场的改变引起温度场的变化。因此,在进行结晶器流场温度场模拟时,必须考虑钢液的凝固,否则将影响计算结果。
此外,本文还模拟分析了浸入式水口出口倾角、水口壁厚、水口出口面积比、浸入深度、拉坯速度、过热度对宽厚板坯结晶器内钢液流动方式、传热和凝固的影响。通过分析不同工况下的结晶器内温度场和凝固壳厚度分布情况,合理设计水口的结构参数和操作工艺,提高拉坯速度和铸坯质量,指导连铸生产。
As the heart of slab conticaster, mould is the most important part of it. Many scholars, at home and abroad, pay more attention to the fluid flow and temperature distribution in slab continuous casting mold. But most of them simulate the process without regard to the influence of shell thickness and mushy zone. Or deal the heat transfer and the flow with segregated solver, The modeling solidification and melting of commercial FLUENT package and program designed is apply in this paper. The SIMPLE algorithm namely the Semi-Implicit Method for Pressure Linked Equations is employed to solve the equations. The flounce, because of the existence of shell thickness and mush zone, can be analyzed exactly.
Based on the mould of continuous casting for manufacture of steel slab that made in Qinhuangdao Shouqin metallic material Co., Ltd., the flow and temperature fields are simulated. The mushy zone is treated as a“pseudo”porous medium with porosity equal to the liquid fraction, and velocity is attention to it too. Shell thickness’velocity is equal to pull velocity. Because of shell thickness and mush zone, the flow zone is smaller and vortex center is rising, and the characteristic of flow field is evidence. Compared the change above, the fluctuation on top is larger, where near the SEN. And the temperature filed also change. The fluid solidification should be considered when we solve fluid flow problems. Or it must be wrong.
Furthermore, the research analyze the effect of outlet angle of SEN, thickness of SEN, the ratio of SEN’s outlet area to inlet, immersion depth of SEN, casting speed, superheat to flow field, temperature field and solidification in this thesis. Therefore, that simulating temperature distribution and shell thickness in mold under different working condition and design rational SEN and casting technology parameters will have useful guiding significance to the process of continuous casting.
引文
1干勇,仇圣桃,肖泽强.连续铸钢过程数学物理模拟.北京:冶金工业出版社, 2001:1-2
2朱苗勇,刘家奇,肖泽强.板坯连铸结晶器内钢液流动过程的模拟仿真.钢铁, 1996, 31(8): 23
3包燕平,张涛,蒋伟,等.板坯连铸结晶器内钢液流场的三维数学模型.北京科技大学学报, 2001, 23(2): 106-110
4马范军,文光华,李刚.板坯连铸结晶器内钢液流动数值模拟.金属学报, 2000, 36(4):399-402
5 R. M. Mchdavid. Fluid Flow and Heat Transfer Behavior of Top-Surface Flux Layers in Continuous Casting. [Master Thesis, University Illinois at Urbana Champaign].1994: 1-80
6 Huang X, Thomas B G, Najjar F M. Modeling superheat removal during continuous casting of steel slabs. Met. Traus B, 1992, 23B: 339-356
7 Brain G. Thomas. Simulation of Longitudinal off Corner Depression in Continuous Casting Steel Slabs. I&SM, 1990, (4): 57-68
8 Flint P J. A three-dimensional finite difference model of heat transfer fluid flow and Solidification in the continuous slab caster. Proc. 73 Steelmaking Conf. Iron and Steel Society, Warren dale, PA, 1990:57
9刘旭东,朱苗勇,邹俊苏,等.连铸板坯凝固传热过程的计算机模拟.材料与冶金学报, 2002, 1(3): 195-199
10 Baokuan LI and Fumitaka TSUKIHASHI. Effect of Static Magnetic Field Application on the Mass Transfer in Sequence Slab Continuous Casting Process[J].ISIJ Imitational,2001,41(8):844-850
11张胤,贺友多,刘建辉,等.板坯连铸机结晶器内流动及传热过程的数学模型.钢铁研究, 2001. 10(5): 31~34
12张胤,贺友多,刘建辉,等.拉坯速度对结晶器内钢液流动和温度分布的影响.过程工程学报, 2009, 9(1): 317-320
13杨秉俭,苏俊义.连铸结晶器中三维紊流流动的数值模拟.西安交通大学学报, 1997, 31(4): 67-72
14 J·舍克里.冶金中的流体流动现象.彭一川,徐匡迪,樊养仪,译.北京:冶金工业出版社, 1985: 144-157
15 Qiaotong Lu, Rongguang Yang, Xinhua Wang, et al. Water modeling of mold powder entrapment in slab continuous casting mold. Journal of University of Science and Technology Beijing, 2007, (05): 399-404
16 D. Gupta and A. K. Lahiri, A water model study of the flow asymmetry inside a continuous slab casting mold, Metall. Mater. Trans. B, 1996, 27B: 757
17 D. Gupta and A. K. Lahiri, Water-modeling study of the surface disturbances in continuous slab caster. Metall. Mater. Trans. B, 1994, 25B, : 227
18 Y. P. Bao, J. Q. Zhu, W. Jiang, et al. Water modeling research on slag-entrapment in the mould of thin slab continuous caster. J. Univ. Sci. Technol. Beijing, 1999, 21(No.6): 530
19 F. M. Najjar, B. G. Thomas, and D. E. Hershey, Numerical study of steady turbulent flow through bifurcated nozzles in continuous casting. Metall. Mater. Trans. B, 1995, 26B: 749
20蔡临宁,麻向军,杨秉俭,等.铸型型腔充填过程的准三维水模拟实验.西安交通大学学报, 1999, (5): 16-21
21曲英,杨健,徐保美.熔渣下金属熔池流动现象的数学模拟.金属学报, 1990, (3): 10-14
22黄维通,伊炳希,徐保美,等.连铸结晶器内三维流动过程的数值计算方法.北京科技大学学报, 1994, 16(6): 527~531
23杨秉俭,苏俊义.薄板坯连铸结晶器中钢液三维流动的数值模拟.应用力学学报, 2000, 17(1): 18-22
24杨秉俭,苏俊义.连铸结晶器中三维紊流流动的数值模拟.西安交通大学学报, 1997,31(4): 67-72
25文光华,李刚,张建春.高速板坯连铸结晶器内流场温度场的数值模拟.钢铁, 1997, 32(增刊): 691
26 Flint P J. A three-dimensional finite difference model of heat transfer fluid flow and solidification in the continuous slab caster. Proc. 73 Steelmaking Conf. Iron and Steel Society, Warren dale, PA,1990: 238-563
27 Ya MENG, Thomas B G. Heat transfer and solidification model of continuous slab casting. CONID. Metall. Mater. Trans. B, 2003, 34B: 685-704
28杨秉俭,黄尊贤.板坯连铸结晶器内凝固壳的测定和分析.特种铸造及有色合金, 1998, (3):7-9
29朱苗勇,刘旭东.连铸凝固传热过程钢的热物性参数分析. http://www.yjsb.cn/ lw/ lg/lg89.htm, 2001
30张富强,王军,梁祥远.中薄板坯高拉速连铸结晶器平均热流研究.钢铁, 2002, 37(12): 19-20
31张晨,汪钺强.连铸结晶器综合传热系数的定量分析.钢铁研究学报, 2000, 2(12):21~24
32 Hbouttalebei M R, Hasan M, Guthrie R I L. Coupled turbulent flow, heat and solute transfer in continuous casting process. Metallurgical and Materials B, 1995, 26B(4): 731~744
33 Szekely J, Yadoya R T. The physical and mathematical modeling of the flow field in the mold region continuous casting system. Met Trans B, 1973, 4: 1379-1388
34陈克,徐宝升.轮带式连铸机结晶器的流场.北京科技大学学报, 1990, (4): 23-26
35 Thomas B G, Mikaslab-casting machine. L J,Najjar F M. Simulation of flow inside a continuous slab-casting machine. Met Trans B, 1990, 21B: 387-400
36 Jung-Eui LEE, Jung—Kyu YOON, Nam HON. 3-dimentional mathematical model for the analysis of continuous beam blank casting using body fitted coordinate system. ISU International, 1998, 38(2): 132-141
37 Abotalebi M R, Hasan M, G uthrie R I L. Coupled turbulent flow, heat and solute transport in continuous casting processes. Metal Traus B, 1995, 26B: 731~744
38 Yang Hongliang, Zhao Liangang, Zhang Xingzhong et al. Development ofmathematical model based on coupling fluid flow and solidification in continuous casting of steel. Proc Int Conf Modell Simul Metall Eng Mater Sci, 1996: 361
39 Yang H L, zhao L G. Mathematical simulation on coupled flow, heat and solute transport in slab continuous casting process. Metallurgical and Materials B, 1998, 29B(12): 1345-1355
40蔡开科.连续铸钢原理与工艺.北京:冶金工业出版社, 1994: 1-356
41李强,朱清香,杨志宏.用边界元法求解非稳态非线性凝固传热问题.东北重型机械学院学报, 1996, 20(2): 99-103
42许志强,罗秉臣,王亚洲.连铸坯在结晶器中表面热流分布规律的研究.重型机械, 1997, (5): 16-20
43 Zhang J M. Postdoctoral Study Report. University of Science and Technology Beijing, 1999: 22-26
44 Jung-Eui Lee, Heung Nam Han. A fully coupled analysis of fluld flow heat transfer and stress in continuous round casting. ISIJ International, 1999, 39(5): 435-444
45张炯明,王立峰,王新华,等,板坯连铸结晶器传热系数.金属学报, 2003, 39(12): 1281-1284
46温正,石良辰,任毅如. FLUENT流体计算应用教程.北京:清华大学出版社, 2009:
1-461
47韩占忠,王敬,兰小平. FLUENT流体工程仿真计算实例与应用.北京:北京理工大学出版社, 2004: 1-203
48沈颐身,李保卫,吴懋林.冶金传输原理.北京:冶金工业出版社, 2000.384-294
49周俐.冶金传输原理.北京:冶金工业出版社, 2009: 10-223
50王雅贞,张岩.新编连续铸钢工艺与设备.第2版.北京:冶金工业出版社, 2007: 215-492
51陈家祥.连续铸钢手册.北京:冶金工业出版社, 1990: 158~293
52 Harste K, Jablona A, Schwerdtfeger K, 4th Int. Conf. Continuous Casting, Brussels, Belgium, Verlag Stahleisen,, Dusseldorf, 1988, 2: 633-644
53陈素琼.板坯连铸轻压下热—力耦合分析和质量研究.钢铁冶金, 2004: 9-13
54罗春胜,彭琦,仇东丽.宽板坯连铸结晶器浸入式水口结构优化的研究.钢铁研究, 2007, 35(6): 33-36
55罗春胜.宽板坯连铸结晶器三维流场与温度场的数值模拟. [武汉科技大学硕士学位论文]. 2007: 1-70
2朱苗勇,刘家奇,肖泽强.板坯连铸结晶器内钢液流动过程的模拟仿真.钢铁, 1996, 31(8): 23
3包燕平,张涛,蒋伟,等.板坯连铸结晶器内钢液流场的三维数学模型.北京科技大学学报, 2001, 23(2): 106-110
4马范军,文光华,李刚.板坯连铸结晶器内钢液流动数值模拟.金属学报, 2000, 36(4):399-402
5 R. M. Mchdavid. Fluid Flow and Heat Transfer Behavior of Top-Surface Flux Layers in Continuous Casting. [Master Thesis, University Illinois at Urbana Champaign].1994: 1-80
6 Huang X, Thomas B G, Najjar F M. Modeling superheat removal during continuous casting of steel slabs. Met. Traus B, 1992, 23B: 339-356
7 Brain G. Thomas. Simulation of Longitudinal off Corner Depression in Continuous Casting Steel Slabs. I&SM, 1990, (4): 57-68
8 Flint P J. A three-dimensional finite difference model of heat transfer fluid flow and Solidification in the continuous slab caster. Proc. 73 Steelmaking Conf. Iron and Steel Society, Warren dale, PA, 1990:57
9刘旭东,朱苗勇,邹俊苏,等.连铸板坯凝固传热过程的计算机模拟.材料与冶金学报, 2002, 1(3): 195-199
10 Baokuan LI and Fumitaka TSUKIHASHI. Effect of Static Magnetic Field Application on the Mass Transfer in Sequence Slab Continuous Casting Process[J].ISIJ Imitational,2001,41(8):844-850
11张胤,贺友多,刘建辉,等.板坯连铸机结晶器内流动及传热过程的数学模型.钢铁研究, 2001. 10(5): 31~34
12张胤,贺友多,刘建辉,等.拉坯速度对结晶器内钢液流动和温度分布的影响.过程工程学报, 2009, 9(1): 317-320
13杨秉俭,苏俊义.连铸结晶器中三维紊流流动的数值模拟.西安交通大学学报, 1997, 31(4): 67-72
14 J·舍克里.冶金中的流体流动现象.彭一川,徐匡迪,樊养仪,译.北京:冶金工业出版社, 1985: 144-157
15 Qiaotong Lu, Rongguang Yang, Xinhua Wang, et al. Water modeling of mold powder entrapment in slab continuous casting mold. Journal of University of Science and Technology Beijing, 2007, (05): 399-404
16 D. Gupta and A. K. Lahiri, A water model study of the flow asymmetry inside a continuous slab casting mold, Metall. Mater. Trans. B, 1996, 27B: 757
17 D. Gupta and A. K. Lahiri, Water-modeling study of the surface disturbances in continuous slab caster. Metall. Mater. Trans. B, 1994, 25B, : 227
18 Y. P. Bao, J. Q. Zhu, W. Jiang, et al. Water modeling research on slag-entrapment in the mould of thin slab continuous caster. J. Univ. Sci. Technol. Beijing, 1999, 21(No.6): 530
19 F. M. Najjar, B. G. Thomas, and D. E. Hershey, Numerical study of steady turbulent flow through bifurcated nozzles in continuous casting. Metall. Mater. Trans. B, 1995, 26B: 749
20蔡临宁,麻向军,杨秉俭,等.铸型型腔充填过程的准三维水模拟实验.西安交通大学学报, 1999, (5): 16-21
21曲英,杨健,徐保美.熔渣下金属熔池流动现象的数学模拟.金属学报, 1990, (3): 10-14
22黄维通,伊炳希,徐保美,等.连铸结晶器内三维流动过程的数值计算方法.北京科技大学学报, 1994, 16(6): 527~531
23杨秉俭,苏俊义.薄板坯连铸结晶器中钢液三维流动的数值模拟.应用力学学报, 2000, 17(1): 18-22
24杨秉俭,苏俊义.连铸结晶器中三维紊流流动的数值模拟.西安交通大学学报, 1997,31(4): 67-72
25文光华,李刚,张建春.高速板坯连铸结晶器内流场温度场的数值模拟.钢铁, 1997, 32(增刊): 691
26 Flint P J. A three-dimensional finite difference model of heat transfer fluid flow and solidification in the continuous slab caster. Proc. 73 Steelmaking Conf. Iron and Steel Society, Warren dale, PA,1990: 238-563
27 Ya MENG, Thomas B G. Heat transfer and solidification model of continuous slab casting. CONID. Metall. Mater. Trans. B, 2003, 34B: 685-704
28杨秉俭,黄尊贤.板坯连铸结晶器内凝固壳的测定和分析.特种铸造及有色合金, 1998, (3):7-9
29朱苗勇,刘旭东.连铸凝固传热过程钢的热物性参数分析. http://www.yjsb.cn/ lw/ lg/lg89.htm, 2001
30张富强,王军,梁祥远.中薄板坯高拉速连铸结晶器平均热流研究.钢铁, 2002, 37(12): 19-20
31张晨,汪钺强.连铸结晶器综合传热系数的定量分析.钢铁研究学报, 2000, 2(12):21~24
32 Hbouttalebei M R, Hasan M, Guthrie R I L. Coupled turbulent flow, heat and solute transfer in continuous casting process. Metallurgical and Materials B, 1995, 26B(4): 731~744
33 Szekely J, Yadoya R T. The physical and mathematical modeling of the flow field in the mold region continuous casting system. Met Trans B, 1973, 4: 1379-1388
34陈克,徐宝升.轮带式连铸机结晶器的流场.北京科技大学学报, 1990, (4): 23-26
35 Thomas B G, Mikaslab-casting machine. L J,Najjar F M. Simulation of flow inside a continuous slab-casting machine. Met Trans B, 1990, 21B: 387-400
36 Jung-Eui LEE, Jung—Kyu YOON, Nam HON. 3-dimentional mathematical model for the analysis of continuous beam blank casting using body fitted coordinate system. ISU International, 1998, 38(2): 132-141
37 Abotalebi M R, Hasan M, G uthrie R I L. Coupled turbulent flow, heat and solute transport in continuous casting processes. Metal Traus B, 1995, 26B: 731~744
38 Yang Hongliang, Zhao Liangang, Zhang Xingzhong et al. Development ofmathematical model based on coupling fluid flow and solidification in continuous casting of steel. Proc Int Conf Modell Simul Metall Eng Mater Sci, 1996: 361
39 Yang H L, zhao L G. Mathematical simulation on coupled flow, heat and solute transport in slab continuous casting process. Metallurgical and Materials B, 1998, 29B(12): 1345-1355
40蔡开科.连续铸钢原理与工艺.北京:冶金工业出版社, 1994: 1-356
41李强,朱清香,杨志宏.用边界元法求解非稳态非线性凝固传热问题.东北重型机械学院学报, 1996, 20(2): 99-103
42许志强,罗秉臣,王亚洲.连铸坯在结晶器中表面热流分布规律的研究.重型机械, 1997, (5): 16-20
43 Zhang J M. Postdoctoral Study Report. University of Science and Technology Beijing, 1999: 22-26
44 Jung-Eui Lee, Heung Nam Han. A fully coupled analysis of fluld flow heat transfer and stress in continuous round casting. ISIJ International, 1999, 39(5): 435-444
45张炯明,王立峰,王新华,等,板坯连铸结晶器传热系数.金属学报, 2003, 39(12): 1281-1284
46温正,石良辰,任毅如. FLUENT流体计算应用教程.北京:清华大学出版社, 2009:
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