基于热量平衡的大方坯连铸传热数学模型研究

Research on heat equilibrium-based heat transfer mathematic model for bloom continuous casting

基于热量平衡原理建立了大方坯连铸过程的传热数学模型,通过对二冷区的分段和联立方程组求解,可以快速获得二冷区指定位置铸坯的坯壳厚度、表面温度、凝固潜热、散热等热状态参数。以某钢厂的大方坯连铸机生产45号钢为研究背景的数值模拟和现场测温表明,铸坯断面尺寸为260mm×340mm,铸机拉速为0.5m/min、0.6m/min时,模型的计算结果符合凝固规律,计算温度与实测温度的误差小于2%,计算结果可为大方坯动态轻压下工艺的优化提供可靠的依据。

On the basis of principle of heat equilibrium the heat transfer mathematic model has been established for bloom continuous casting. By dissection of the secondary cooling zone and solution of the simultaneous equations such a few parameters at the specified location of the secondary cooling zone as the thickness of the strand shell, surface temperatures, latent heat of solidification and heat dissipation can be quickly achieved. Numerical simulation and on-site temperature measurements on the basis of the bloom continuous caster at a specific steel-making plant show that under the casting conditions of the section area of the bloom 260 mm × 340 mm, casting speed 0. 5 m/min and 0.6 m/rain the results of simulation calculation are completely in agreement with the law of solidification and deviation between the calculated temperature and the on-site measured one is less than 2 %. The results of calculation can be used as the basis for optimization of the operating process of soft reduction of the bloom.