全水口自旋流连铸水口钢水流动行为

摘要： 全水口自旋流连铸是从源头上优化结晶器流场的重要技术，利用数值模拟手段，研究了拉坯速度和旋流发生装置入口尺寸对自旋流连铸钢水流动行为的影响。研究表明，拉坯速度和入口尺寸对水口内钢水旋流具有重要影响，旋流强度随拉速增大而增大，随入口面积增大而减小，且随钢水向下流动近似呈线性减小；当旋流装置入口流速为1.1m/s时，水口内钢水旋转速度达4.10m/s，受旋流影响水口中心钢水反重力向上流动；水口流场沿径向可分为湍流各向同性区、各向异性区和近壁区，随入口速度增加湍流各向异性区范围增大。研究明确了全水口自旋流连铸过程钢水旋流行为的关键控制因素，为旋流连铸的参数优化提供了支撑。

Flow behavior of molten steel in SEN during full nozzle self swirling flow continuous casting

Abstract： Full nozzle self swirling flow continuous casting is an important technology to optimize the mold flow field from the source. Numerical simulations were carried out to investigate the influence of casting speed and inlet area of the swirling flow generator on steel flow behavior in SEN (submerged entry nozzle). The results show that the casting speed and the inlet area have important effects on the swirling steel flow in SEN. The swirl intensity increases with the increase of casting speed, decreases with the increase of inlet area, and decreases approximately linearly with the downward flow of molten steel in SEN. The swirling flow velocity can reach 410m/s with the generator inlet velocity of 11m/s. Due to the effect of swirling flow, molten steel at the nozzle center moves upwards. The flow field in SEN along the radial direction can be divided into three regions, namely, the isotropic turbulent fluctuation region, the anisotropic turbulent fluctuation region, and the near wall region. With the increase of inlet velocity, the anisotropic turbulent fluctuation region increases. This study reveals the key control factors on steel flow behavior in a full nozzle self swirling flow continuous casting process, which provides a good support for the parameter optimization of the swirling flow continuous casting process.