结晶器内连铸坯凝固过程的有限元数值模拟

Finite Element Numerical Modeling on the Solidification of Continuous Casting Billet in Mold

建立了结晶器内连铸坯凝固过程的有限元数学模型．在坯壳表面边界条件中引入与气隙相关的传热模型修正平均热流量方程，研究了铸坯角部气隙对坯壳凝固行为的影响．模拟结果表明：铸坯角部形成的气隙显著地降低了坯壳表面的换热，使得铸坯偏角区成为热节区．此热节区是铸坯凹陷、裂纹等缺陷乃至漏钢事故发生的诱因．

A finite element mathematical model was developed to simulate the solidification of continuous casting billet in mold. A gap-dependent heat transfer model was introduced into the boundary condition at the shell surface to modify the average heat flux equation. The influence of air gap at the billet corner on the solidification of continuous casting billet was investigated. The simulation results indicate that the heat flux is apparently reduced by air gap at the billet corner,and that a hot spot is formed in the off-corner which very likely is the cause of inducing the off-corner depression,cracks and breakout.