【摘要】 本文采用双方程(κ-ε)紊流模型和热平衡方程把连铸坯凝固传热作为钢液紊流和传热耦合问题求解。对闭式浇铸系统轮式连铸机的凝固进行了数值计算,其结果与水模型实验和现场实机浇铸实验相吻合。结果表明:水口突扩引起的水口射流股周围回流区过长是“水口挂钢”和初生坯壳厚度突变的主要原因,并与该铸机在开发研究中遇到的铸坯矫裂漏钢和其它质量问题有密切联系。挂钢大小和坯壳厚度突变程度主要取决于回流区长度,还受过热度和拉坯速度等因素的影响。提出了相应的改进措施,这对其他细薄断面连铸机的开发研究也有现实意义。更多还原

【Abstract】 Mathematical model of turbulence (K-e) and energy balance equation were employed to study the conjugation of molten steel flow and heat transfer in solidification process of continuous casting. Numerical prediction on that process of wheel type caster with enclosed pouring system has been made. The results are well consistent with the measured and observed facts of experiments in a water model and a prototype machine. The results show that the too long recirculating zones around nozzle jet induced by sudden expansion at nozzle outlet are one of the main causes for development of nozzle-attached crust and consequent abrupt change of shell thickness, which are directly linked to the breakout and other quality problems faced in R&D of wheel type caster of this kind. The extent of the crust attached to the nozzle and the abruptness of shell thickness depend mostly on length of the recirculaton zone, and at some less degree on super heat and casting speed. Improving measures based on this study are presented, some of them are also applicable to other near-net-shape casters under development.更多还原