水口结瘤对板坯连铸结晶器钢水行为影响的数值模拟

以230 mm×1 600 mm板坯连铸机结晶器为研究对象,采用CFD数值模拟的计算方法,建立了VOF模型,研究了连铸水口结瘤对钢渣界面波动与钢液流动行为的影响。研究结果表明,当水口无结瘤时,结晶器内流场为典型的双环流形貌。当水口有结瘤时,结晶器内水口两侧会出现严重的非对称流,结瘤侧流股范围小,非结瘤侧流股范围大。水口不结瘤一侧动能增大导致结晶器下涡心位置下降,会使钢液冲击深度增大;水口结瘤一侧水口因涡心位置较高,加剧了弯月面处的波动和钢渣表面的波动紊乱。结瘤情况下的钢液波动较大,最大波动差为4.03 mm;不结瘤情况下钢液波动较平稳,最大波动差为1.4 mm。

Numerical simulation of the effect of nozzle nodule on the behavior of molten steel in slab continuous casting mold

Taking the mold of 230 mm×1 600 mm slab continuous casting machine as the research object, the VOF model was established by CFD numerical simulation method, and the influence of continuous casting nozzle nodule on steel slag interface fluctuation and molten steel flow behavior was studied. The results show that the flow field in the mold is a typical double circulation morphology when there is no nodule at the nozzle.When there is nodule at the nozzle, there will be serious asymmetric flow on both sides of the nozzle in the mould, with a small range of nodule side stream and a large range of non-nodule side stream. The increase of kinetic energy on the non-nodular side of the nozzle leads to the decrease of the vortex center under the mold, which will increase the impact depth of the molten steel. In addition, due to the high vortex center on the nodule side of nozzle, the fluctuation of meniscus surface and steel slag surface is disordered. In the case of nodules, the steel fluid fluctuates greatly, with the maximum fluctuation difference of 4.03 mm. Without nodules, the fluctuation of molten steel is relatively stable, with the maximum fluctuation difference of 1.4 mm.