This paper presents the results of a computer simulation and laboratory experiments carried out to describe the hydrodynamics of steel active flow in the tundish. One of the parameters describing the correct influence of FCDs on the tundish operation is the description of the active flow zone (dispersed plug flow and well mixed volume flow). The facility under investigation is a single-nozzle tundish designed for casting concast slabs. Computer simulations of liquid steel flow were performed using the commercial program Ansys-Fluent. For the validation of the numerical model and verification of the hydrodynamic conditions occurring in the examined tundish furniture variants, obtained from the computer simulations, a physical model of the tundish was employed. During laboratory tests simulating the process of steel flowing through the tundish, E type RTD curves were recorded, which were then juxtaposed with results obtained from computer simulations. In order to obtain a complete hydrodynamic picture in the tundish furniture variants tested, the computer simulations were performed for both isothermal and non-isothermal conditions.

The paper presents computational modelling of the liquid steel flow in a wedge‐type one‐strand slab tundish. The modelling was extended on the variance of liquid flow under a subflux turbulence controller (STC) and a gas permeable barrier on the tundish bottom. Commercial software was used for solving the mathematical model of the casting process. For the description of interactions between the continuous phase (liquid steel) and the discrete phase (inert gas), an Euler‐Lagrange description was chosen. The internal space of the subflux turbulence controller had the shape of a truncated cone, made according to a new design. Three locations for the gas permeable barrier were simulated and the flow rate of inert gas blown into the liquid steel was varied in the range from 10 to 30 Nl/min. The numerical modelling was validated by experimental tests which were carried out in an industrial wedge‐type tundish of a Polish steel plant. The industrial experiments included a direct sequence of heats of different chemical analysis in the course of the casting operation.The computations provided liquid steel flow maps, residence time distribution curves (RTD), and the volumes of particular flow types (stagnant, plug and ideal mixing flows), which characterize the effect of argon blowing and the subflux turbulence controller on liquid steel flow in the tundish. As a result, the industrial tundish operation was optimized.

The paper presents investigation results related to a tundish furnished with a flow control devices (FCD). The facility under investigation is a one‐strand tundish used for casting concast slabs. To evaluate the influence of FCDs on the pattern of liquid steel flow, an industrial and a laboratory experiments (physical and numerical simulation) were carried out. In collaboration with Vesuvius, a refractory materials manufacturer, and the ISD Czestochowa Steelworks Ltd., pilot industrial tests were carried out. Based on data acquired from the industry, a glass tundish model on a scale of 1:2.5 was made. A tundish in the form of virtual models was prepared for numerical simulations using the Gambit 2.4 software program. Commercial software Ansys‐Fluent® was used for solving the mathematical model of the liquid steel flow. From the industrial and laboratory experiments, results were obtained, which provided a basis for plotting curves describing the steel mixing process in the tundish. In addition, the computer simulations provided also a valuable source of information about the flow directions, flow intensity and temperature of the liquid steel, represented in the form of maps.

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Numerical simulation of liquid steel flow and behaviour of non-metallic inclusions in onestrand slab tundish with subflux turbulence controller and gas permeable barrier A. Cwudziń ski* The paper presents computation results from the simulation of liquid steel flow in a one-strand slab tundish used in a Polish steel plant. This is a wedge type tundish with a depression in the bottom of the discharge zone. Fluent software was used for solving the mathematical model of the casting process, and Euler-Lagrange description was chosen for the description of interactions between the continuous phase (liquid steel) and the discrete phase (inert gas). To verify the mathematical model and the numerical simulation results, test results obtained from industrial experiments were applied. The internal geometry of the facility under consideration was changed by two types of flow control devices, a subflux turbulence controller and a gas permeable barrier mounted on the tundish bottom. A number of variants were tested including flowrate and position of the argon. For all variants of modification, the quantity of non-metallic inclusions removed from liquid steel has been obtained.