Abstract: According to an object of study on mould for continuous casting 950 kg/min H-beam bloom, with using established three dimensional geometry models by FLUENT software the casting speed (0.6-1.2 m/s) with nozzle submerged depth 125 mm and 175 mm on transferring characteristics of liquid steel in mould has been simulated and studied. Results show that with different casting speed the patterns of liquid steel flow in mould for H-beam bloom are similar, but with increasing casting speed the jet impacting depth of liquid steel and the flow velocity of liquid at free surface in mould increase, the melting status of mould powder is tending to improvement, and the fluctuation of liquid free surface in mould and the impact effect of liquid flow on solidified shell are tending to increase. While with increasing casting speed, removal ratio of inclusions with different sizes from liquid all decreases, among them the removal ratio of large-sized inclusions decreases markedly, as the casting speed increases from 0.6 m/min to 1.2 m/min the removal ratio of 100 μm inclusions decreases from 16% to 10% , and in simulating condition the removal ratios of 20-100 μm inclusions are 4% to 16%.

Key words: H-Beam Bloom Casting, Mould, Transferring Characteristics of Liquid Steel, Numerical Simulation

摘要： 以950 kg/m H型连铸坯结晶器为研究对象,采用FLUENT软件建立三维几何模型,模拟研究了水口浸入深度125 mm和175 mm时拉速（0.6~1.2 m/s）对结晶器内钢液传递特性的影响。结果表明,不同拉速条件下H型坯结晶器内钢液流态相似,但随着拉速的增大,结晶器内钢液流股冲击深度增大和结晶器自由表面流速增大,保护渣熔化状况有改善趋势,同时结晶器液面波动和钢水对凝固坯壳的冲刷有增大趋势。而各粒径夹杂物上浮去除率随拉速的增大而降低,其中大颗粒夹杂物去除率降低显著,当拉速由0.6 m/min增至1.2 m/min时,100μm夹杂物的去除率由16%降至10%。该模拟条件下,20~100μm夹杂物去除率在4%~16%。

关键词: H型坯连铸, 结晶器, 钢液传递特性, 数值模拟