双挡坝中间包内钢液的流动行为

通过采用水模拟和数值模拟分别对中间包不同结构进行全因素试验,研究了双挡坝结构对钢液流动行为的影响,着重探讨了不同类型的双挡坝中间包内钢液的流动状态和速度分布。结果表明:低坝应设置在高坝后,顶端钢液流速将减小29%,降低浇注末期发生卷渣的概率;低坝应与高坝流钢孔同高,钢液的平均停留时间可达到最大稳定值;高低坝距离差为40~160mm时,流体流动状态较稳定,低坝后无漩涡产生。分析认为:中间包入口区和出口附近均为强湍流状态,其他区域均为过渡流状态,入口区利于夹杂物的碰撞长大,应至少保证该区域长度大于中间包长度的1/4,出口区强湍流易产生大夹杂物导致水口堵塞,应控制在出水口附近0.25m的区域内。

Flow Characteristics of Liquid Steel in Slab Casting Tundish With Double Dam

The experiments for all factors were carried out to study the influence of reactor??s structure on the fluid flow characteristics by means of water simulation and numerical simulation. The steel flow condition and velocity distribution in the tundish with different kinds of double dams were mainly discussed. The results indicate that when the low dam is set behind the high dam, the surface velocity near the low dam top is reduced by 29% and probability of slag entrapment is decreased at the end period of casting. The top of low dam should be flush with the top of hole in the high dam. The optimal distance between the high dam and the low dam is 40-160 mm, in which the flow state is more stable and no vortex flow is generated behind the low dam. The analysis of numerical simulation shows that the flows in of the inlet and outlet regions of the tundish are strong turbulence, while other regions in the tundish are transition flow. The strong turbulence in the inlet region help inclusions grow up by collision, so the region length should be more than a quarter of the length of tundish. However, the strong turbulence in outlet region leads to nozzle clogging easily, so it should be restricted within a 0. 25 m radius of outlet.