Abstract: The key step to cause the granulation of gas quenching molten slag is the granulated liquid slag droplet quick cooling and solidifying, and during slag droplet cooling process the main manners of heat transfer are convection and radiation. Based on established mathematical model for slag droplet cooling process, the rule of effect of radiation on slag droplet cooling process is emphasized studied by 4th order Runge-Kutta method. Results show that the slag droplets cooling are undergoing three phases including liquid phase cooling and nucleating, release of latent heat, and solid phase cooling； as the heat transfer through radiation is ignored, it takes 606 ms for temperature of slag droplet (/% : 29. 94FeO, 2. 05 Fe₂O₃,42. 18CaO, 9. 33MgO, 15. 92SiO₂, 2. 09MnO, 1. 25 Al₂O₃, 2. 24P₂O₅) in nitrogen at 293 K decreasing from 1 723 K to 1 073 K, as compared with that considering the cooling time simultaneously by convection and radiation, it increases by 17. 2%. The results indicate that in calculating cooling rate of slag droplet the heat transfer through radiation can not be ignored.

摘要： 液态钢渣气淬粒化成功的关键在于粒化后液滴的快速冷却固化,渣滴冷却过程的传热方式主要为对流和辐射在构建的渣滴冷却过程数学模型的基础上,利用4阶Runge-Kutta方法重点研究了辐射对渣滴冷却过程的影响规律。结果表明,渣滴冷却经历液相冷却成核、潜热释放和固相冷却3个阶段;在没有考虑辐射换热情况下,渣滴(/%:29.94FeO、2.05Fe₂O₃、42.18CaO、9.33MgO、15.92SiO₂、2.09MnO、1.25Al₂O₃、2.24P₂O₅)在293 K氮气中由1 723 K降温至1 073 K需要606 ms,比综合考虑对流和辐射时的冷却时间延长了17.2%,说明在计算渣滴温降速率时辐射换热的影响不容忽视。

关键词: 辐射, 对流, 气淬, 渣滴, Runge-Kutta法, 数值求解