A phenomenological model for the reduction of iron ore/carbon composite pellets in a multi-layer bed rotary hearth furnace has been developed. A single pellet model has been scaled up to a multi-pellet layer version in a computationally efficient way. The multi-layer pellet bed has been conceived as single column of identical pellets in a rectangular enclosure, assuming symmetry of the pellet bed in horizontal direction. The column walls are considered opaque with respect to heat transfer but allow heat radiation to reach the pellet surface through multiple reflections from the wall. The time-temperature-transformation and time-temperature-chemical heat absorption contours are presented to provide a better understanding of the reduction process. Finally, the net heat flux and carbon monoxide generation, emerging from the multi-layer bed system has been generated, which may be used as source and sink terms for CFD simulations in the free board of the RHF.

中文翻译：

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铁矿石/碳复合球团矿在单层和多层床转底炉中还原行为的计算研究

已经开发了在多层床转底炉中还原铁矿石/碳复合球团的现象学模型。单个颗粒模型已以计算效率高的方式扩展为多颗粒层版本。假设颗粒床在水平方向上对称，多层颗粒床被设想为矩形外壳中相同颗粒的单列。柱壁在传热方面被认为是不透明的，但允许热辐射通过壁的多次反射到达颗粒表面。提供了时间-温度-转换和时间-温度-化学吸热等值线，以更好地了解还原过程。最后，净热通量和一氧化碳的产生，