120t转炉旋流氧枪的射流搅拌特性

Jet stirring characteristics of nozzle twisted lance in 120t converter

熔池流动状态及反应速度是实现转炉高效冶炼的关键,主要取决于氧气射流与熔池的相互作用及底吹搅拌强度。建立了120t转炉旋流氧枪的三维全尺寸几何模型,利用数值模拟研究了不同旋流角旋流氧枪的射流特性,并对比分析了其对转炉熔池的冲击搅拌效果。结果表明,随着旋流角的增大,氧气流股的射流核心区长度不断减小,射流中心距氧枪轴线距离增大,氧枪射流交汇点距喷孔出口距离不断增大,射流聚合现象被抑制;当旋流角由0°增加至15°时,氧气射流的冲击深度减小了40%,冲击半径增加了13%;熔池纵截面上的高速区域分布在冲击凹坑附近,横截面上的高速区域分布在冲击凹坑及相邻凹坑连接处延长线外部区域。

The flow state and reaction rate of the molten pool is the key to realize efficient smelting in the converter steelmaking process,which is mainly determined by the interaction of the oxygen jet with the bath and bottom blowing stirring intensity.A three-dimensional full-scale geometric model of the nozzle twisted lance in a 120 tconverter was established.The jet characteristics of nozzle twisted lance with different swirl angles were studied by numerical simulation,and the stirring effect of impacting molten bath was compared and analyzed.The results show that with the increase of swirl angle,the length of the jet core is decreased,the distance between the jet center and the axis of oxygen lance is increased,the distance between the intersection point of the jet and the outlet of the orifice is improved,and the jet aggregation phenomenon is inhibited.When the swirl angle increases from 0° to 15°,the impact depth of the oxygen jet is decreased by 40%,and the impact radius is improved by 13%.The high-speed area on the longitudinal section of the molten bath is distributed near the impact dent,while the high-speed area on the cross-section is distributed in the external area of the extension line at the impact dent and the connection of adjacent dents.