Influence of Large-Scale Vortex Movement in Lower Recirculation Zone on Instable Flow Field in the Mold
Influence of Large-Scale Vortex Movement in Lower Recirculation Zone on Instable Flow Field in the Mold
复制标题
下回流区大规模涡运动对结晶器内不稳定流场的影响
DOI：
10.2355/isijinternational.isijint-2018-160
复制
发表时间：
2018-09
影响因子：
1.8
通讯作者：
Qiang WANG
中科院分区：
文献类型：
--
作者：
Xiaowei ZHU;Dewei LI;Chunlei WU;Tretiak OLEKSANDR;Qiang WANG
板坯连铸过程中，结晶器内的流场不稳定，会导致最终产品出现缺陷。为了研究钢水在结晶器内的不稳定流动，采用非定常Reynolds-average （URAN）方法研究了结晶器内钢水的不稳定流动。结果表明，下循环区大尺度涡运动是造成流场不稳定的主要因素。这些涡流改变了下部再循环区钢液的流出量。从喷嘴一侧出口排出的钢水到达一定深度后回流到喷嘴底部，而从另一侧出口排出的钢水则深深地流入液池。这将导致铸件内部缺陷的不对称分布。这些涡旋也影响钢水的半月板水平波动。它们改变了下循环区的逆流方向和压力场，影响了气流撞击窄面上的位置和角度。研究结果可为稳定结晶器内流场提供依据。
During continuous casting of slab, the flow field in the mold is unstable, which will lead to defects in final products. To investigate the instability of molten steel in the mold, an unsteady Reynolds-average (URAN) method is used to study the unstable flow of molten steel in the mold. The results show that the large-scale vortex movement in the lower recirculation zone is a major factor causing the instability of flow field. These vortexes change the outflow of molten steel in the lower recirculation zone. Molten steel discharging from one side of the nozzle outlet reaches a certain depth, it refluxes to the bottom of nozzle, while it discharging from the other outlet flows deep into the liquid pool. This will cause an asymmetric distribution of internal defects in the casting productions. These vortexes also affect the meniscus level fluctuations of molten steel. They change the reverse flow direction and pressure field in the lower recirculation zone, which affect the position and the angle of stream impinging on the narrow face. The paper could provide a basis for stabilizing the flow field in the mold.