Mathematical Modeling of the Fluid Hydrodynamics and Refining Effects in a Gas-Stirred Ladle with Pulsed Bottom Blowing

Purging plugs are commonly used in the secondary refining process, which determines the fluid hydrodynamics and refining effects of the ladle. This study proposes a blowing approach to enhance flow field disturbance and mass transfer. The experiment, designed to validate the numerical simulation, involved the use of UDF (user-defined function) to describe bubble expansion and the variation of gas blowing. The results indicated that the pulsed bottom blowing method was more effective in producing tiny bubbles. Owing to the smaller fluctuation amplitude for the pulsed bottom blowing, the energy dissipated by slag layer fluctuations decreases. Compared to the pulsed bottom blowing, the proportion of the slag eye area of the steady bottom blowing is 12 pct larger. Furthermore, the pulsed bottom blowing causes an intermittent flow field. This discontinuity stirring energy input is conducive to its transmission and dissipation. Besides, the mixing time of pulsed bottom blowing exceeds 5 pct larger than that of the steady bottom blowing. These findings have practical implications for enhancing the flow hydrodynamics of liquid steel and controlling bubble diameter by the purging plug within the pulsed bottom blowing in the ladle, which is also suitable for stirring reactors with gas blowing.