浸没喷吹高温烟气流动过程的数值模拟

熔池内部是一个复杂的高温环境,内部的高温烟气流动过程对熔炼效果有着重要影响。针对熔池内高温烟气流动过程,采用数值模拟方法,分析了高温烟气喷出时产生气泡的生长、上升过程中的速度变化和在熔池内的温度变化,以及不同速度下连续喷吹时熔池内部的气液两相混合状态等,结果表明：高温烟气喷吹产生的气泡在喷枪管口生长变大,初始形状为半圆型逐渐变为椭圆型紧贴喷枪管壁两侧上升,上升过程中下边界向内凹陷,呈一个“伞帽状”上升,上升的高度越高向内凹陷的程度越深,冲出液面时破碎成多个小气泡。不同喷吹速度的高温烟气在喷枪管口生成气泡的过程中速度迅速减小,生成的气泡上升过程中速度基本稳定于0.25 m/s,气泡在熔池中运动时其内部温度在短时间内快速下降到300 K,内部温度场有明显的梯度变化。在1 s内高温烟气喷吹速度越大熔池内的气液两相混合状态越好。

Numerical of High Temperature Flue Gas Flow Process by Submerged Injection

The interior of the molten pool is a complex high-temperature environment, and the internal high-temperature flue gas flow process has an important impact on the smelting effect. Aiming at the flow process of high-temperature flue gas in the molten pool, the growth of bubbles generated by high-temperature flue gas injection, the change of velocity in the rising process and the change of temperature in the molten pool, as well as the gas-liquid two-phase mixing state in the molten pool during continuous injection at different speeds are analyzed by numerical simulation. The results show that the bubbles generated by high-temperature flue gas injection grow larger at the nozzle of the spray gun, The initial shape is semi-circular and gradually becomes elliptical. It rises close to both sides of the spray gun pipe wall. During the rising process, the lower boundary is concave inward and rises in an "umbrella cap shape". The higher the rising height is, the deeper the inward depression is, and it breaks into multiple small bubbles when it rushes out of the liquid level. The velocity of high-temperature flue gas with different injection speeds decreases rapidly in the process of generating bubbles at the nozzle of the spray gun. The velocity of the generated bubbles is basically stable at 0.25 m / s. when the bubbles move in the molten pool, their internal temperature drops rapidly to 300 K in a short time, and there is an obvious gradient change in the internal temperature field. Within 1 s, the higher the injection speed of high-temperature flue gas, the better the gas-liquid two-phase mixing state in the molten pool.