Abstract: This study established a three-dimensional transient gas-liquid two-phase flow model based on a 150-tonne converter to investigate the influence of the number of clogged bottom-blowing elements on the stirring efficiency of the molten pool. The numerical simulation results were further validated against actual converter operating conditions. The findings revealed that the primary reason for the deteriorated flow characteristics in the molten pool under multiple clogged tuyeres was the overall reduction in stirring energy input from the bottom-blowing gas. Specifically for this converter system, when the number of clogged tuyeres reached three, the numerically simulated mixing time increased from 150.6 s to 219.3 s, a significant increase of 45.62%. This numerical result was in good agreement with water model experiments, indicating that prompt furnace bottom maintenance and tuyere replacement should be considered under such circumstances. At the same bottom-blowing intensity, the effective stirring area of a single inner-ring tuyere was 0.919 m2, while that of a single outer-ring tuyere was 1.651 m2. The combined effective area achieved through the synergy of inner and outer ring tuyeres was 2.940 m2, which was 14.4% greater than the sum of their individual areas. Clogging disrupted this synergistic stirring effect. A single clogged tuyere had a negligible impact on the distribution of dead zones. However, when tuyeres in both the inner and outer rings were clogged, dead zones became more numerous and concentrated. With 3 and 4 clogged tuyeres, the dead zone volume reached 3.703 and 5.946 m3, accounting for 17.31% and 27.79% of the total molten pool volume, respectively. An industrial plant trial was conducted based on the numerical simulation scheme showed that key performance indicators deteriorated as the number of clogged tuyeres increased. With three clogged tuyeres, the average end-point oxygen content reached 0.0669wt%, which was 22.1% higher than that under non-clogged conditions. Concurrently, the total iron content in the slag reached 19.44%, a 24.5% increase compared to the non-clogged baseline.

Key words: bottom-blowing element, numerical simulation, number of clogged elements, stirring efficiency, end-point oxygen content

摘要： 本工作以150 t转炉为原型，建立三维瞬态气液两相流模型，探究底吹元件堵塞数量对熔池底吹搅拌效能的影响规律，并基于数值模拟结果对比转炉底吹实际堵塞工况。研究结果表明，多元件堵塞导致底吹供气搅拌能整体衰减，是其影响熔池流动行为的核心原因。针对该转炉底吹体系，底吹元件的堵塞会降低总搅拌能，当堵塞数量达到3个时，熔池混匀时间增幅达45.62%，此时需及时进行炉底维护或更换元件。堵塞还破坏了内外环元件间的协同搅拌效应，使有效作用面积利用率下降，单个内、外环元件有效面积分别为0.919和1.651 m2，二者协同带动面积较面积之和提升14.4%，而堵塞会削弱这一优势。单元件堵塞对死区分布影响有限，但内外环同时堵塞或堵塞数量增至3个和4个时，死区体积分别占熔池总体积的17.31%和27.79%，且呈现集中分布。工业试验进一步验证，随堵塞元件数增多，终点平均氧含量与渣中全铁含量均显著上升，堵塞3个元件时较未堵塞分别恶化22.1%和24.5%。

关键词: 底吹元件, 数值模拟, 堵塞元件数量, 搅拌效能, 终点氧含量