Numerical, Physical, and Industrial Studies of Liquid Steel Chemical Homogenization in One Strand Tundish with Subflux Turbulence Controller

Abstract

Chemical homogenization of liquid steel is one of the basic parameters defining quality of final products. The 95% chemical homogenization level is a required minimum that defines the effective dissolution of all the components introduced to the liquid steel. The object of investigation was a one-strand wedge-type tundish designed for casting slabs. For the set zone of alloy feeding, numerical simulations, laboratory experiments (with a isothermal physical water model) and industrial experiments were carried out. During the research project, a method for the hybrid introduction of an alloy addition to liquid steel has been developed, which combines the pulse and the step methods. From the performed computational fluid dynamics (CFD) computations, laboratory and industrial trials, fields of liquid steel flow, maps of water motion, behavior of non-metallic inclusions during industrial alloying process, mixing curves and time mixing characterize influence of using subflux turbulence controller (STC) on alloying process in the tundish have been obtained. In the tundishes with STC and a low dam, a reduction in mixing time was noted.

Influence of Hydrodynamic Structure on Mixing Time of Alloy Additions with Liquid Steel in One Strand Tundish

“…However, feeding alloy additions to liquid steel during the course of continuous casting at the tundish stage is limited by two basic factors, liquid steel temperature (20-30°C above liquidus temperature of heat) and the limited time of additional treatment of liquid steel in tundish (average residence time of liquid steel). The investigation results reported earlier confirmed that there were real grounds for developing a technology for efficient feeding alloy additions to liquid steel during continuous casting process [7][8][9]. The present study reports the results of investigation into the hydrodynamic pattern forming in the tundish and its effect on the time of alloy addition mixing with liquid steel.…”

“…1), are presented in Table 1. All of the proposed FCDs are described in detail in papers [7][8][9]. zone, the feeding stream is directed towards the upper liquid steel surface.…”

Numerical and Physical Modeling of Liquid Steel Flow Structure for One Strand Tundish with Modern System of Argon Injection

“…The next investigation stage included numerical simulations of the behavior of liquid steel under isothermal conditions for the proposed tundish furnishing variants. A detailed description of the hydrodynamic pattern occurring in the low‐dam tundish working space is provided in the work . Figure shows the stream lines and velocity vectors of liquid steel flow structures forming in the plane located through porous plug no.…”

“…Whereas the maximum cell volume equals 5.4 × 10 −5 m 3 . The numerical model and the physicochemical quantities for the liquid steel and argon are described in detail in the previous work . For describing the turbulence motion of liquid steel and argon, the realizable k–ϵ model was adopted.…”

“…Uniform small bubbles effectively support process of non‐metallic inclusions flotation from liquid steel . For the non‐isothermal conditions of steel flow through the tundish, the magnitudes of heat fluxes on particular tundish walls and bottom have been determined according to the previous work . Further, density of liquid steel was described by polynomial function as reported by work .…”