针对板坯连铸过程中, 结晶器内钢水在行波磁场(电磁搅拌)作用下的流动行为, 采用水银作为模拟工质进行模型实验, 并结合基于流场雷诺应力模型的数值模拟, 分析钢水的流动规律及其对连铸工艺的影响. 研究结果显示, 施加行波磁场(电磁搅拌)时, 结晶器内钢水注流的对称性发生了改变, 进流被电磁力推向一侧, 在结晶器内形成全区域的水平环流, 破坏了通常钢水注流所呈现的规律性上下环流; 在结晶器上部近液面区域内, 水口两侧的环流分别被压缩到靠近水口或窄面的位置, 从而使结晶器内流场趋于紊乱的三维流态; 同时, 液面波动幅度增大, 在钢水注流与电磁力反向的一侧, 液面波动更加剧烈.
This paper presents a mercury model experiment and coupling numerical simulation with Reynolds time-average model on molten metal flow in the mold of continuous casting of slab. The purpose is to study the influence of a traveling magnetic field (electromagnetic stirring) on the metal flow in the mold. The result shows that, in the mold, the stirring force from the traveling electromagnetic field makes the molten metal form a horizontal circumfluence, leading to destroy of the originally regular circumfluence. In the whole mold, the flow is three dimensional and non-symmetrical. Furthermore, the traveling magnetic field strengthens fluctuation of meniscus. The fluctuation is stronger on the side where the nozzle flow is opposite to the electromagnetic force.
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