炉鼻子内气氛回流的数值研究

Numerical Study of Gas Reverse Flow in Snout

带钢热镀锌工艺往往需要抑制炉鼻子内锌灰的向上运动,这是由于锌灰容易黏附在带钢表面,影响镀层质量,另外锌灰回流到退火炉中将影响上游工艺流程。本文结合某钢铁厂提出的一种炉鼻子内保护气体外循环装置,利用计算流体力学方法对炉鼻子内部气氛流场进行模拟分析,得出了抽气流量对气氛流动、全局回流及压力平衡的影响;采用正交分析,明确了抽气流量的显著影响作用,并总结出最优参数组合,掌握该组合下的回流规律。本研究对炉鼻子体外循环装置的运行方案提供了理论指导。

The hot-dip galvanizing process of strip steel often needs to restrain the upward movement of zinc ash in the snout,because the zinc ash is easy to adhere to the surface of strip steel,affecting the coating quality.In addition,the zinc ash flowing reversely to the annealing furnace will affect the upstream process.Combined with an external circulation device of protective gas in the snout proposed by a steel plant,the gas flow field in the snout was simulated and analyzed by Computational Fluid Dynamics,and the influence of extraction flow rate on gas flow,global reverse flow and pressure balance was discussed;The orthogonal analysis was carried out to determine the significant influence of the extraction flow,and the optimal parameters was summarized.The mechanism of the reverse flow under this condition was be mastered.This study provides theoretical guidance for the operation scheme of the external circulation device of the snout.