Mathematical Modeling Of Fluid Flow, Heat Transfer And Solidification In Continuous Caster

The mold is the last liquid metal reactor and the first billet forming device in thesteel manufacturing process. The flow field of molten steel in the mold has animportant impact on the heat transfer of molten steel, free surface fluctuation, thebubble and inclusion removal. The temperature field in the mold influences thetemperature distribution of billet and the distribution of solidified shell thickness. Bothflow and temperature play a decisive role in the quality of continuous casting billet. Acomprehensive and in-depth understanding of the flow and heat transfer of molten steelin mold is very important to the smooth production and high efficiency of continuouscasting.Take the slab continuous casting mold as the research object in this paper, buildthe transient mathematical model of molten steel flow and solidification in mold withmulti physics coupling software COMSOL Multiphysics by the method of finiteelement. Studied the impact of casting speed, slab width, immersion depth and outletangle of the SEN(Submerged Entry Nozzle) and superheat on the molten steel flow andheat transfer in the mold. And the model results were verified with the empiricalformula calculation results. The simulation results show that:(1)The basic flow characteristic of molten steel in the mold is: the molten steelimpinges the narrow face of the mold and forms the upper and lower two circulationsafter outflow from the SEN outlet.(2)The impact depth and the impact velocity increased with the increase of castingspeed and slab width, vortex moving downward and liquid steel flow rate of the freesurface also increased at the same time.(3)Immersion depth has little effect on the impact speed, but the impact depthincreased with the increase of immersion depth, vortex moving downward with theincrease of immersion depth at the same time.(4)The impact depth and the distance from vortex to the free surface increased with the increase of outlet angle of the SEN, while the impact velocity and the liquidsteel flow rate of the free surface decreased with the increase of outlet angle of theSEN.(5)The slab solidified shell thickness decreases about2.3mm when the castingspeed increases0.2m/min; and the slab solidified shell thickness decreases about0.8mm when the superheat increases5degrees.