Large Eddy Simulation on the Two‐Phase Flow in a Water Model of Continuous Casting Strand with Gas Injection

Abstract

The Large Eddy Simulation (LES) turbulent model coupled with VOF multiphase model and Lagrangian Discrete Phase Model (DPM) is applied to investigate the gas–liquid two‐phase flow and bubble distribution. The drag force, lift force, virtual mass force, and pressure gradient force are incorporated in the current developed model, and the lift force is added via user defined subroutine. The influence of the drag force, the lift force, bubble size, and gas flow rate on the distribution of bubbles and flow field are investigated. The PIV measurements are employed to validate the mathematical model. The results show that the gas injection can affect the flow field and bubble behavior directly. The impingement point on the narrow face and vortex core of the upper recirculation zone moves upward with the increase of gas flow rate. The drag force has distinct influences on the bubble distribution and flow field. The interaction induced by the lift force cannot be ignored. Without the consideration of the lift force, a larger flow velocity will be predicted. Moreover, the lift force has significant effect on the bubble distribution at mold thickness direction, especially the larger bubbles.

Study on the Spatial Distribution of Argon Bubbles in a Steel Slab Continuous Casting Strand

“…The vortex moved toward the meniscus in the upper circulation zone with the increasing of the argon flow rate. [58] Figure 19 shows the flow velocity and the average diameter of argon bubbles on the meniscus of the mold at different argon flow rates. The speed near the SEN increased with the increasing of the argon flow rate since the buoyancy of bubbles on the molten steel was enhanced.…”

“…The vortex moved toward the meniscus in the upper circulation zone with the increasing of the argon flow rate. [ 58 ]…”

Single bubble breakup in the flow field induced by a horizontal jet—The numerical simulation

“…where p is pressure, is gravitational acceleration, and is external force. The physical properties, including the density ρ and viscosity μ are determined by volume‐weighted averages.…”

“…Smirnov et al used LES method in high‐Reynolds number bubbly ship‐wake flows simulations, and bubble distributions for mixing layers and wakes were obtained only consuming reasonable computing resources. Chen et al used LES combined with VOF and discrete phase model to study the flow pattern and bubble distribution of air injection into water tank, where the influence of drag force and lift force on bubble motion was analyzed. Asiagbe et al simulated microbubbles in a vertical turbulent channel flow of water using LES, fluid structures affecting bubble behavior, and the influence of bubble on the continuous flow are obtained.…”

Bubbly Mold Flow in Continuous Casting: Comparison of Numerical Flow Simulations with Water Model Measurements

“…In many simulations, even very recent ones, the standard k-ε turbulence model is used for the turbulence modeling of the liquid phase or of the mixture of liquid and gas. [7,9,21,22] Recently some groups have been using large eddy simulations for multiphase mold flow simulations, [8,23,[25][26][27] while hybrid turbulence models such as the scale adaptive simulation (SAS) model are very rare. [23] For the results presented in this publication, two turbulence models are used: the realizable k-ε [28,29] (RKE) and the SAS model.…”