1∶1 mold water simulation of optimization of submerged entry nozzle of super large round bloom
In order to optimize the metallurgical effect of the super large round bloom continuous casting mold,a full-scale large round bloom(≥ϕ800 mm)mold water modeling platform was established.Under a fixed immersion depth,the flow field and liquid level behavior in the mold due to different submerged entry nozzle(SEN)structures were quantitatively and qualitatively evaluated by observing the liquid level fluctuation,monitoring the average sur-face velocity,and conducting ink display flow field and water-oil simulated slag entrapment experiments.The results show that the free liquid surface velocity decreases gradually with the SEN port angle continuously down-ward,and the simulated slag entrapment situation also decreases gradually,but the free liquid surface is too calm when the SEN angle is downward 15°.When the SEN angle is upward 15°,the liquid level in the area from the middle of the mold to the mold wall is more active,accompanied by more serious liquid surface exposure and slag entrapment situation.The SEN with runway,round,inverted trapezoidal and rectangular flared side port shapes were analysed.It can be seen that the SEN with round port shape will make the jet concentrated,resulting in the sur-face velocities and level fluctuations are much larger than the other SEN port shapes,but also lead to a very serious slag entrapment and liquid surface exposure phenomenon,the slag entrapment of the length of the time proportion can be as high as 98%.However,the rectangular flared shape makes the jet more dispersed so that the surface velocities are small,and the level fluctuations in the middle region of the mold are high.The free liquid surface can be active in a large area without liquid surface exposure,and the slag entrapment occurs only 27%of the time.At the same time,the liquid surface flow rate of the rectangular flared nozzle does not change significantly as the casting speed increases.The five-port rectangular flared shape with a 15° upwards are much better for controlling the flow of molten steel in a super large round bloom mold than the five-port runway shape with a 15° upwards currently in use.It is more conducive to the surface quality and internal quality control of the bloom.
super large round bloomwater modeling platformSEN port angleSEN port shapeflow stateslag entrapmentmold
NETL
NSTL
万方数据
