Pulse-step method for liquid steel alloying in one strand slab tundish

Abstract

The minimisation of the duration of ladle furnace treatment on the ladle furnace station and transferring part of the technological operations to the tundish might intensify the steel production process. The present paper reports results concerning a new method of feeding alloy additions intended to be used during the continuous casting process. For continuous casting tundishes, it seems possible and rational to correct the chemical composition of steel or to feed low melting point microalloys and non-metallic inclusion modifiers. The object of investigation was a single strand tundish. Computer simulation of the liquid steel flow and alloy addition behaviour in turbulent motion conditions was done using the Ansys-Fluent computer program. The numerical model employed in the computations was verified by industrial (non-isothermal conditions) and laboratory (isothermal conditions) tests. In all tundish equipment variants, except for variant no. 3, a reduction in the mixing time was achieved as against the tundish currently used in industrial conditions.

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.…”

“…Computer simulation of the liquid steel flow, tracer and alloy addition behaviour in turbulent motion conditions was done using the Ansys-Fluent ® computer program. A detailed description of the mathematical model and the employed numerical procedure is presented in studies [8][9][10]. The liquid steel flows into the tundish at a mass flow rate of 34.43 kg/s.…”

“…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.…”

Control and Design of the Steel Continuous Casting Process Based on Advanced Numerical Models

“…Research conducted by many authors [12][13][14][16][17][18][19][20][21] shows a very good compliance between simulations of the flow of liquid steel through the tundish, using turbulent flow models k-ε, and tests performed on water models and tests in industrial conditions. Most numerical calculations are conducted on the basis of the Reynolds-averaged Navier-Stokes equations (RANS) method, which allows the average rate of turbulent flow in the tundish to be determined.…”

“…Most numerical calculations are conducted on the basis of the Reynolds-averaged Navier-Stokes equations (RANS) method, which allows the average rate of turbulent flow in the tundish to be determined. However, the application of the Large Eddy Simulation (LES) method, along with the Smagorinsky-Lilly turbulent model, allows us to determine the instantaneous velocity field of the steel inside the tundish [12,16,18,22]. Not only are the selection of the method of computing the rate of liquid steel flow through the tundish and the selection of the main model parameters key to the values of liquid steel velocity vectors in individual nodes of the finite element mesh, but they are also crucial to the temperature distribution within the whole tundish volume.…”