Modeling of Transient Two-Phase Flow in a Continuous Casting Mold Using Euler-Euler Large Eddy Simulation Scheme

Abstract

Euler-Euler Large Eddy Simulation (EELES) scheme has been developed to simulate the two-phase flow of argon gas and molten steel in slab continuous casting mold. The Euler-Euler approach is used to describe the equations of motion of the two-phase flow. The drag force, lift force and virtual mass force are incorporated in this model. Both turbulence of argon gas and molten steel are simulated using large eddy simulation (LES). Simulation results agree acceptably well with the water model experimental measurements of instantaneous flow structures. The flow pattern in the lower recirculation zone is expected to be asymmetrical between the left and right sides of the mold. The flow pattern is changeover; the direction of flow deviation is different from time to time. The time intervals for changeover appeared to vary randomly. The long-term asymmetry in the lower roll is due to the turbulent nature instead of the variation of other operating parameters. The turbulent flow in the mold includes multiple vortices. Those vortexes make the flow field to be more complex. Two typical transient flow structures, consisting of clockwise or counterclockwise rotational direction vortices, are found in the upper roll.

Effect of Argon Injection in Meniscus Flow and Turbulence Intensity Distribution in Continuous Slab Casting Mold Under the Influence of Double Ruler Magnetic Field

“…Few studies are reported on the on the consequence of gas on transient fluid dynamic behaviour. Liu et al 10) simulated two-phase flow of argon gas and molten steel in slab continuous casting mold using Euler-Euler Large Eddy Simulation (EELES) scheme. Steady k-ε turbulence computational results of Bai and Thomas 11) revealed that increasing argon gas volume fraction or bubble diameter bends the jet angle more upward and also increases turbulence.…”

Instability and Periodicity of Asymmetrical Flow in a Funnel Thin Slab Continuous Casting Mold

“…According to recent plant observations and detections, the distribution of argon bubbles and non-metallic inclusions captured by solidified shell in the rolled steel plates was intermittent and asymmetric; [8][9][10] suggesting that the fluid flow inside the mold was unsteady and instable. Several physical modeling studies 8,10,[11][12][13][14][15][16][17] have been carried out to reproduce the asymmetrical and oscillating fluid flow inside the casting mold.…”

“…Several physical modeling studies 8,10,[11][12][13][14][15][16][17] have been carried out to reproduce the asymmetrical and oscillating fluid flow inside the casting mold. Gupta et al 11,12) found that the flow pattern in the lower recirculation zone of a traditional slab mold was asymmetric and oscillating about the central plane with a random period.…”

“…2, obtained from the k-ε model, the predicted flow pattern inside the present calculation mold was symmetric and stable, failure to explain the asymmetrical and oscillating fluid flow inside the mold. In recent studies, 8,10,22,23) the large eddy simulation (LES) has been successfully applied to obtain the transient asymmetrical flow inside the mold. Yuan et al 22) combined LES and particle image velocimetry (PIV) measurements in a scaled water model, finding good agreement between both types of data.…”

“…RamosBanderas et al 23) studied the fluid flow of water in a slab mold using LES and PIV, founding the asymmetrical flow and the flow pattern changed with time as a consequence of the vertical oscillation of the jet core. Recently, authors developed different LES models for the single phase (molten steel) flow 8) and the two-phase (molten steel and argon gas) flow 10) inside the slab mold, respectively. Both of simulation results agree acceptably well with the water model experimental measurements of instantaneous flow structures.…”