大方坯径向水口旋流效应及其对凝固的影响

通过改变水口侧孔钢水流动方向可以控制结晶器内钢水流动与换热。采用流体动力学与凝固模拟方法对比研究了浸入式四分径向水口不同出流方向对大方坯连铸结晶器内流动、传热和凝固行为的影响。结果表明，侧孔方向对浇注过程结晶器内钢水的流动与凝固行为有显著影响。当水口侧孔水平旋转角度为30°时，结晶器内形成较好的水平旋流，可以有效降低侧孔出流钢水对坯壳的冲刷作用，并有利于结晶器内自由液面过热度的提高。比较不同侧孔出流角度发现，利用普通径向四分水口在一定安装角度下的旋流效应不仅对于初生坯壳的均匀生长以及自由液面的冶金效果产生有利影响，还可能在不改变水口结构条件下获得类似结晶器电磁搅拌的旋流效应。

Swirling flow effect of radial outlet nozzle for bloom and #br# its effect on initial solidification

 The flow and heat transfer of molten steel in the mold can be controlled by changing the outflow direction of the molten steel in the side hole of the nozzle, and the effects of different outlet directions of submerged entry nozzles on the fluid flow, heat transfer, and solidification behavior in the bloom continuous casting mold were analyzed by using hydrodynamics and solidification simulation methods. The results showed that the direction of side hole had a significant effect on the flow and solidification behavior of molten steel in the mold during casting. when the horizontal rotation angle of the nozzle side hole was 30°, a favorable horizontal swirling flow can be produced in the mold, which can effectively reduce the jet impingement of molten steel flowing from the side hole on the solidifying shell, together with an increasing meniscus temperature. Comparing the different outlet angles of side holes, it was also found that the swirling flow effect of ordinary radial quadruple nozzle produced under certain installation angle not only has a beneficial effect on the uniform growth of primary shell and the metallurgical effect of the mold, but also can obtain the swirling flow effect similar to that of M EMS even without changing the nozzle structure.