Physical modeling of gas-liquid interfacial fluctuation in a thick slab continuous casting mold with argon blowing

Abstract

Combining with the physical model of level fluctuation in a thick slab continuous casting mold with the cross-section of 1500 mm×280 mm and argon blowing, the rationalities of estimating the level fluctuation by three traditional quantitative approaches were discussed, and the effects of gas flowrate, casting speed, and the immersion depth of submerged entry nozzle (SEN) on the level fluctuation were also investigated. As a result, it seems that three traditional quantitative approaches are not very suitable for estimating the level fluctuation in a mold with argon blowing, so a new approach for estimating level fluctuation in the mold with argon blowing was presented. The experimental results show that the level fluctuation is mainly in the region around the nozzle wall. When the casting speeds are larger than a certain value, there is the escape of large bubbles near the nozzle wall, which causes an obvious increase of level fluctuation. Furthermore, optimal process parameters, viz., the gas flowrate of 6 NL/min, the casting speed of 1.1 m/min, and the immersion depth of 170 mm, are presented to restrain the level fluctuation by a physical model.

Keywords

slabs / continuous casting / molds / level fluctuation / modelling

References

[1] Teshima T., Kubota J., Suzuki M., Ozawa K., Masaoka T., Miyahara S. Influence of casting conditions on molten steel flow in continuous casting mold at high speed casting of slabs. Tetsu-to-Hagané, 1993, 79(5): 576.

[2] Y. Wang, W. Zheng, L.X. Zhu, J.N. Mu, and M.Y. Zhu, Water model study on argon blowing of SEN of cast mold at No.1 Steelmaking Plant of Baosteel, Baosteel Technol., 2000, No.6, p.26.

[3] H.Y. Chen, X.Z. Na, and X.Q. Ji, Statement of liquid steel flowage in mould and optimization of submerged entry nozzle shape, Continuous Cast., 2001, No.5, p.1.

[4] Bao Y.P., Tian N.Y., Xu B.M. New submerged entry nozzle in thin slab caster. J. Univ. Sci. Technol. Beijing, 2002, 24(3): 262.

[5] Zhang S.J., Zhu M.Y., Zhang Y.L., Zheng S.G., Cheng N.L., Song J.X. Study on mechanism of entrapment in slab continuous casting mould with high casting speed and argon blowing. Acta Metall. Sin., 2006, 42(10): 1087.

[6] He K.N., Xiao J.G., Wei Y.H., Sun Y.H., Liao W.T. Experimental research on structure of submerged entry nozzle and operation parameter optimization for wide slab continuous casting mold. Iron Steel, 2008, 43(1): 26.

[7] Lu Q.T., Yang R.G., Wang X.H., Zhang J.M., Wang W.J. Water model experiments on surface characteristics of slab mold flow patterns. J. Baotou Univ. Iron Steel Technol., 2006, 25(1): 13.

[8] Lu Q.T., Yang R.G., Wang X.H., Zhang J.M., Wang W.J. Water modeling of mold powder entrapment in slab continuous casting mold. J. Univ. Sci. Technol. Beijing, 2007, 14(5): 399.

[9] Wan X.G., Han C.J., Cai K.K., Yang S.B., Yan X.M., Gu W.A. Experimental research of submerged entry nozzle of slab continuous casting. Iron Steel, 2000, 35(9): 20.

[10] X.X. Qi, F. Yue, and G.L. Liu, Experimental study of water model on liquid steel flowing in mould of slab casting, Continuous Cast., 2003, No.5, p.15.

[11] Wang Z., Mukai K., Ma Z.Y., Nishi M., Tsukamoto H., Shi F. Influence of injected Ar gas on the involvement of the mold powder under different wettabilities between porous refractory and molten steel. ISIJ Int., 1999, 39(8): 795.

[12] Lei H., Xu H.H., Zhu M.Y., Gan Y., Liu X., Ni M.S., Liu J.Q. Mechanism and control of slag entrapment in high casting mould. Iron Steel, 1999, 34(8): 20.

[13] Lei H., Zhu M.Y., He J.C. Physical modeling of the vortex phenomenon in continuous casting mould. Chin. J. Process Eng., 2001, 1(1): 36.

[14] Zheng S.G., Zhu M.Y. Study on mechanism of large bubble formation in slab continuous casting mould with argon blowing. Steel Res. Int., 2008, 79(12): 918.

[15] Singh V., Dash S.K., Sunitha J.S., Ajmani S.K., Das A.K. Experimental simulation and mathematical modeling of air bubble movement in slab caster mold. ISIJ Int., 2006, 46(2): 210.

[16] Lu Q.T., Wang X.H., Yu H.X., Zhang J.M., Wang W.J. Calculation of F value and relationship between F value and slag entrapment in a slab continuous casting mold. J. Univ. Sci. Technol. Beijing, 2007, 29(8): 811.