板坯连铸38 t扩容中间包控流装置优化的数值模拟和应用

通过数值模拟,对钢厂250 mm×2 000 mm板坯连铸原29 t扩容至38 t中间包进行控流装置优化。研究了挡墙、挡坝的个数和位置对中间包内钢液流场及停留时间分布(RTD)曲线的影响,综合考虑了中间包冶金效果及生产成本,为现场提出了稳流器+挡墙+挡坝控流装置的最优设计方案,该方案使中间包活塞区比例达到77.1%,死区比例降至4.2%。现场采用该结构后非稳态浇铸期间生产的管线钢非金属夹杂物合格率由88%提高到95%,明显提高了中间包的冶金功能。

Numerical Simulation and Application on Optimization of Flow Control Device in 38 t Expansion Tundish for Casting Slab

The optimization of flow control device in 38 t expansion tundish from original 29 t for casting 250 mm X 2 000 mm slab at steelworks has been carried out by numerical simulation. The effect of number and position of dam and weir on flow field and residual time distribution ( RTD) curves of liquid in tundish has been studied. With comprehensive consideration of tundish metallurgical effect and production cost, the optimum design for control flow devices- current regulator + dam + weir is proposed. With the optimum structure the volume fraction of plug flow region in tundish is up to 77. 1% , the volume fraction of dead region decreases to 4. 2%. With using this structure in situ the qualified ratio of non- metallic inclusions in pipeline steel produced in non-stable casting condition increases to 95% from original 88% , obviously to increase the metallurgical function of tundish.