Simulation Of Slab Vertical Combination Electromagnetic Brake

As the core of the development of China's iron and steel industry,the trend of continuous casting technology mainly includes the high efficiency and high quality of production.Improving the casting speed is the key to improve the production efficiency of continuous casting.EMBr technology is vital to ensure the increase of casting speed.Ruler-EMBr is the most representative type of mold electromagnetic brake.Its braking range covers the entire width of the slab,and its braking effect is affected by the pole position.To solve this problem,this thesis studies the behavior of EMBr.Based on the basic principle of electromagnetic brake technique,a new pattern of electromagnetic brake device was proposed.Numerical simulation was conducted to investigate the behavior of molten steel flow,fluctuation of steel/slag interface and brake effect in continuous casting slab mold with Vertical Combination Electromagnetic Brake(VC-EMBr)and EMBr-ruler.The physical model for describing the level fluctuation behavior of liquid metal in the mold with VC-EMBr and Ruler-EMBr were set up.The thermal experiment was conducted to study the behavior of level fluctuation.Main researches are following:(1)Magnetic field that generated by VC-EMBr is H-shaped at the center of the mold.There is almost no magnetic field distribution away from the pole coverage.The difference between peak and saddle value increases,With excitation current increasing.When the excitation current is 1000A,the difference between the two values is only 0.023 T.(2)Under the same process parameters,the vertical magnetic pole arrangement has a better flow control effect when it is 0.45m away from the water outlet,among the three kinds of VCEMRr.In this form,the maximum velocity of steel/slag interface is 0.093 m/s,the height of meniscus is 0.008 m and the maximum of narrow-surface turbulence kinetic energy is 0.00823 m2/s2.(3)Compared with Ruler-EMBr,VC-EMBR can control the fluid velocity at different casting speed.When the casting speed increased from 1.6 m/min to 2.0m/min,the maximum velocity of steel/slag interface increased from 0.156 m/s to 0.213 m/s with Ruler-EMBr.Under the action of VC-EMBr,the maximum flow rate at the steel/slag interface increased from 1.11 m/s to 1.69 m/s when the casting speed increased from 1.6 m/min to 2.0 m/min.(4)The fluctuation of steel/slag interface is less affected by the change of nozzle angle.The meniscus height decreases from 0.0149m to 0.0121m,Under the effect of VC-EMBr,When the mould angle increases from-10°to-20°.(5)The lower magnetic flux density is not conducive to VC-EMBr control of liquid level fluctuations.When the magnetic induction intensity is 0.21T,the meniscus height is 0.019m,and the maximum velocity of steel/slag liquid surface is 0.148m/s.(6)Through physical simulation,the vertical combination electromagnetic brake under the same process parameters can better control the alloy solution interface height and stability.When Ruler-EMBr and C-EMBr respectively act on the alloy solution,? is equal to 1.184221 and 0.90 mm,respectively.