顶吹浸没熔炼炉中气-渣-铜锍多相流搅拌特性的数值模拟

Numerical modelling of stirring characteristics of gas−slag−copper matte multiphase flow in bath with top submerged lance

采用VOF方法对顶吹浸没熔池中氮气-渣-铜锍的流体动力学特性和搅拌特性进行数值研究。阐明气泡行为和流体速度之间的关系;研究气体入射速度和旋流对流体涡流结构、气体穿透深度和流体速度的影响。结果表明,气泡的形成和上升分别增加和降低流体速度。由于低温气体的注入,流体温度在高度0.43 m和0.52 m处分别呈现V形和W形分布。相比于58 m/s的气体注入速度,气速为98 m/s时气相的时均和最大穿透深度分别增加78.4%和31.9%。由于轴向速度分量的减小,旋流降低气体穿透深度、增加相间动量传递效率、抑制渣相喷溅。

The hydrodynamics and stirring characteristics of the nitrogen-slag-copper matte in a bath with top submerged lance were numerically studied via the volume-of-fluid(VOF)method.The relationship between the bubble behavior and fluid velocity was elucidated.The effects of gas injecting velocity and swirling flow on the fluid vortex structure,gas penetration depth,and fluid velocity were investigated.The results demonstrate that the formation and rising of the bubble increase and reduce the fluid velocity,respectively.The V-shaped and W-shaped temperature distributions of the fluid are observed at the height of 0.43 and 0.52 m,respectively,resulting from the injection of the low-temperature gas phase.Compared to the gas injection velocity of 58 m/s,the time-averaged and maximum penetration depths of the gas phase with the injection velocity of 96 m/s increase by 78.4%and 31.9%,respectively.Swirling flow reduces the gas penetration depth,enhances the momentum transfer efficiency between phases,and suppresses the slag splashing,which is attributed to the reduced axial velocity component.