| In continuous casting process,argon blowing in submerged entry nozzle is often used to prevent clogging,and argon bubble entered the liquid slag may cause the emulsification.At the same time,the flow and heat transfer behavior of the liquid slag will directly affect the quality of the strand.Therefore,the three-dimensional mathematical model for the flow and heat transfer behavior coupled the molten steel and liquid slag has been established in this paper.Based on volume of fluid and discrete phase model,the effect of different process parameters on the flow and heat transfer behavior of liquid slag has been investigated,the results can work as the theoretical basis for optimizing the process parameters.The main conclusions of this paper are as follows:(1)There are two vortexes formed in the liquid slag due to the drag force of molten steel,and the center of the vortex is located near the ideal half-height of liquid slag,the impinging point of steel/slag interface is located in the 500-600 mm area from the center of the SEN.(2)With the increase of argon blowing,the temperature of liquid slag increases and the distribution is more uniform,which is beneficial to the melting of the mold flux.When the flow rate of argon gas increases from 0L/min to 8L/min,the highest temperature in steel/slag interface increases from 1793.08 K to 1794.84 K,and the largest velocity increases from 0.113m/s to 0.118m/s.In conclusion,When the casting speed is 1.2 m/min,the port angle of submerged entry nozzle is 15°,and the submergence depth of the submerged entry nozzle is 160 mm,the preferable flow rate of argon is 4L/min.(3)With the increase of casting speed,when the flow rate of argon is 0 L/min,the velocity and temperature of the liquid slag in the steel/slag interface,the ideal half-height of liquid slag and the nearby top surface of liquid slag increase;but under argon-blowing conditions,the velocity and temperature of the liquid slag in the vicinity of SEN decrease,while those in the mold narrowface increase.(4)With the increase of port angle and submergence depth of SEN,when the flow rate of argon is 0 L/min,the liquid slag temperature continuously decreases,the velocity in the steel/slag interface and the nearby top surface of liquid slag decrease,while that in the ideal half-height of liquid slag increases;Under argon-blowing conditions,the velocity and temperature of the liquid slag decrease,and the distribution is more uniform;(5)With the increase of superheat degree of liquid steel,when the flow rate of argon is 0 L/min,the liquid slag temperature increases,and the velocity continuously decreases;Under argon-blowing conditions,the temperature of the liquid slag increases,the velocity in the vicinity of SEN increases,while that in the mold narrowface decreases.(6)Under argon-blowing conditions,the larger argon blowing rate,the smaller casting speed,port angle,submergence depth and superheat may cause the congealed steel in the narrow area of the mold wideface to the SEN. |
