高拉速小方坯结晶器热流密度模型的开发及应用  

Development and application of heat flux model of high casting speed billet mould

作　　者：向宏学 韩丽敏[1,2] 夏芳勇 武国平 XIANG Hongxue;HAN Limin;XIA Fangyong;WU Guoping(Metallurgical EngineeringBranch,BSIET,Beijing 100043,China;Beijing Metallurgy 3-D Simulation Design Engineering Technology Research Center,Beijing 100043,China)

机构地区：[1]北京首钢国际工程技术有限公司冶金工程分公司,北京100043 [2]北京市冶金三维仿真设计工程技术研究中心,北京100043

出　　处：《连铸》2023年第5期21-27,共7页Continuous Casting

摘　　要：作为连铸生产设备中的关键部件,结晶器对高拉速连铸起到了至关重要的作用。通过建立结晶器平均热流密度计算模型,计算结晶器内控制单元中凝固坯壳、糊状区及液态钢水区对应的质量,进一步计算整个控制单元的散热量,从而得到结晶器的平均热流密度。结合低拉速结晶器实际生产工况参数以及数值模拟分析,验证了模型的准确性。在高拉速工况下分析得到:对于160 mm×160 mm小方坯,在有效结晶器长度为900 mm、拉速为6 m/min的条件下,其结晶器出口处凝固坯壳厚度达到10 mm时,结晶器平均热流密度约为4 200 kW/m^(2);以模型计算得到的热流密度为边界条件,应用有限元仿真软件进行结晶器内钢液凝固状态模拟,计算结果显示凝固坯壳厚度为10 mm。根据平均热流密度计算模型得到的热流密度,结合管内受迫对流换热模型,设计了4种不同的结晶器冷却结构并计算其对流换热系数。利用计算得到的对流换热系数,推导出结晶器各种冷却结构对应的热流密度,得到了适用于高拉速的结晶器冷却结构及水流量。As a key component of continuous casting equipment,mould plays a vital role in high speed continuous casting.By developing a calculation model for average heat flux of mould,the masses and heat transfer quantity of solidified shell,mushy zone area and molten steel area of control unit in mould was calculated,and then the average heat flux of mould is obtained.The accuracy of the model is verified by the actual production parameters of low cast-ing speed and numerical simulation analysis too.Under the condition of high casting speed,the results show that for 160 mmX 160 mm billet,when the effective mould length is 900 mm and the casting speed is 6 m/min,and the so-lidified shell thickness at the exit of the mould reaches 10 mm,the average heat flux of the mould should be 4200 kW/m^(2);Taking the heat flux calculated by the model as the boundary condition,the solidification state of molten steel in the mould was simulated by finite element simulation,and the calculation results showed that the thickness of solidified shell at the exit of the mould was lo mm.According to the heat flux obtained from the average heat flux calculation model,combined with the forced convection heat transfer model in the tube,four different mould cooling structures were designed and their convection heat transfer coefficients were calculated.Based on the calculated con-vective heat transfer coefficient,the heat flux of the mould for the four types of cooling structure is calculated,and then the optimal solution for high casting speed are obtained.

关 键 词：结晶器 高拉速 热流密度 有限元模拟 冷却结构 

分 类 号：TF341.6[冶金工程—冶金机械及自动化]