Abstract: A theoretic analysis is performed with temperature model on transient air cooling and solidification behaviors of a spherical molten slag particle. With considering the variation of thermal conductivity with temperature and the radiation between slag and environment, the temperature distribution and the transient moving of phase-change interface inside the particle are obtained by applying the finite difference method. The effects of variable thermal conductivity, heat transfer boundary condition, slag particle size, air flow rate and initial temperature of the slag particle are discussed. The simulation results indicate that the variable thermal conductivity of the slag extends the solidification process, while the radiation significantly improves the cooling speed. Meanwhile, the solidification process is speeded up with increasing air flow rate and decreasing particle size. The cooling and solidification process is prolonged for the slag particle with higher initial temperature.

Key words: granulate blast furnace slag, phase-change heat transfer, temperature field, phase interface, numerical simulation, model

摘要： 采用温度法模型对高温熔融高炉渣颗粒的相变冷却特性进行了分析，考虑颗粒固液相热导率随温度的变化及颗粒与环境的辐射换热，获得了高温熔渣颗粒内的温度分布以及相界面位置随时间的推移过程。讨论了变热导率、换热条件、颗粒尺寸，冷却流体速度和温度对相变冷却过程的影响，结果表明：热导率的变化使得颗粒冷却凝固时间延长，高温辐射换热极大加快了冷却速率；颗粒直径增加，相界面移动速度降低，凝固时间增加；冷却流体速度增加，温度降低，相界面移动速度增加，凝固时间缩短。

关键词: 粒化高炉渣, 相变换热, 温度场, 相界面, 数值模拟, 模型