Mathematical And Physical Simulation On The Flow Of Liquid Slag In Continuous Casting Mold With Argon Blowing

In order to prevent submerged entry nozzle(SEN)clogging,the nozzle blowing argon technology is often used in continuous casting production,and the argon bubbles entering the mold are also beneficial to the inclusions floating up in the molten steel.When argon bubbles from the molten steel into the liquid slag,a greater impact has been brought to the flow of liquid flux,which in turn affect the melting and heat transfer behavior of the liquid slag.Therefore,it is very important to optimize the process parameters and improve the quality of slab by studying the flow behavior of liquid slag in argon blowing mold and its influencing factors.A 1:0.6(prototype: model)down-scale physical model has been built in this paper,for investigating the effect of argon bubble on flow of liquid flux by using high speed camera under different process parameters,such as casting speed,the depth of SEN,the port angle of nozzle and argon blowing rate.Combined with VOF model and discrete phase model,a three-dimensional mathematical model of argon blowing mold with coupling molten steel and liquid mold flux was established to simulate the flow behavior of the flux before and after the entry of the argon bubbles into the mold powder under different process conditions.The main conclusions are as follows:(1)In the role of molten steel,the liquid slag has a longitudinal direction of the large circulation in the mold,and as the slag layer moves upwards,the velocity of the near-surface liquid slag becomes larger and the fluctuating area increases.(2)With the increase of the casting speed,when the argon is not blown,the flow velocity in the central area of the slag layer increases and the slag fluctuation increases,and the small eddy currents formed near the nozzle also become larger.The flow velocity of the liquid slag near the nozzle is gradually reduced,and the velocity in the narrow area of the mold is increased with argon blowing.(3)With the increase of the depth of SEN and the port angle of nozzle,regardless of argon blowing or not,the slag in the mold flow velocity is reduced,the impact of the latter on the slag flow rate has a relatively large tendency.(4)With the increase of the flux viscosity,while the argon is not blown,the flow velocity distribution of the slag layer at the interface of the steel slag and ideal near surface are reduced,but the velocity of the annular region in the ideal center plane increases.When argon blowing,the slag fluctuation near the nozzle increases,and the fluctuation of the narrow area decreases.(5)Other conditions stay the same,with the increase of argon blowing,slag fluctuations weakened at the mold narrow surface area,and liquid slag flow rate decreased.The fluctuation of the slag layer near the nozzle increases and the flow rate increases.(6)Other conditions stay the same,with the increase of bubble size,the flow velocity of liquid slag near the nozzle increases,and the velocity of the narrow area decreases.