漏斗形结晶器液面流场物理试验与数值模拟分析

当FTSC薄板坯连铸机生产拉速提高到4～6 m/min时,浸入式水口通钢量增加,结晶器内流场扰动加剧,卷渣率提高,对生产顺行及铸坯质量都将产生重大影响。因此,为了解结晶器液面流场,根据实际生产情况,制作了1∶1的结晶器水物理模型,并通过Fluent软件对结晶器液面流场进行了数值模拟,研究了水口浸入深度及拉速对液面流场的影响。结果表明,在水模型物理试验中,水口浸入深度恒定为130 mm时,拉速在4～6 m/min范围内,结晶器表面流速随着拉速的提高而增大,其最大值范围为0.401～0.693 m/s;在6 m/min恒定拉速下,水口浸入深度在130～190 mm范围内,结晶器表面流速随着水口浸入深度的增加而减小,其最大值范围为0.503～0.690 m/s。在数值模拟中,水口浸入深度恒定为130 mm时,拉速在4～6 m/min范围内,结晶器表面流速随着拉速的提高而增大,其最大值范围为0.50～0.75 m/s;在6 m/min恒定拉速下,水口浸入深度在130～190 mm范围内,结晶器表面流速随着水口深入深度的增加而减小,其最大值范围为0.65～0.75 m/s。结晶器表面流速随着距水口中心距离的增大有先增加后减小的规律。

Physical experiment and numerical simulation of flow field on funnel mold surface

When the casting speed of FTSC thin slab is increased to 4-6 m/min, the amount of steel passing through the submerged nozzle increases, the disturbance of flow field in mold intensifies, and the rate of slag entrapent increases, which will have a great influence on the running of production and the quality of slab. Therefore, in order to understand the flow field distribution on the mold surface, this paper made a 1∶1 mold water physical model according to the actual production, and carried out numerical simulation of the flow field on the mold surface through Fluent software, and studied the influence of the submerged entry nozzle depth and casting speed on the flow field on the liquid surface. The results show that the mold surface velocity increases with the increase of the casting speed in the range of 4-6 m/min, and its maximum value ranges from 0.401 m/s to 0.693 m/s when the nozzle immersion depth is constant 130 mm. At a constant casting speed of 6 m/min, the nozzle immersion depth is in the range of 130-190 mm, and the surface velocity of the mold decreases with the increase of the nozzle immersion depth, with the maximum range of 0.503-0.690 m/s. In the numerical simulation, when the nozzle immersion depth is constant at 130 mm and the casting speed is in the range of 4-6 m/min, the surface velocity of mold increases with the increase of the casting speed, and its maximum value ranges from 0.50 to 0.75 m/s. At a constant casting speed of 6 m/min, the nozzle immersion depth is in the range of 130-190 mm, and the surface velocity of the mold decreased with the increase of the nozzle immersion depth, with the maximum range of 0.65-0.75 m/s. The velocity of the mold surface increases first and then decreases with the increase of the distance from the center of the nozzle.