The object of investigation was the one-strand tundish with flow control device such as gas permeable barrier (GPB). The aim of this flow control device was to activate the motion of liquid steel in the tundish longitudinal axis region. Computer simulation of the liquid steel flow and argon behaviour in isothermal turbulent motion conditions was done using the Ansys-Fluent computer program. For the validation of the hydrodynamic patterns obtained from computer simulations, a isothermal tundish glass model was used. Tundish glass model enables the recording of the visualization of fluid medium motion through the particle image velocimetry (PIV) method. Based on computer simulations, the liquid steel flow path lines in the tundish with GPB was obtained. For explain the hydrodynamic phenomena occurring in the tundish working space, the Buoyancy number has been calculated.

In this work, the authors proposed a modification of the working space one-strand tundish adapted for slab casting process. Numerical simulations of liquid steel flow in the considered flow reactor were performed. The tundish is equipped with a dam with a multi-hole filter. Two variants of the filter hole arrangement were tested and their effect on the liquid steel flow hydrodynamic structure in the tundish was examined. The computer calculations results were verified by performing experiments on the water model. The result of numerical and physical simulations an RTD (Residence Time Distribution) type F curve was generated, which define the transition zone between the cast steel grades during the sequential casting process. The results of the researches showed that the modification of a dam with a multi-hole filter affects on the formation of the liquid steel flow hydrodynamic structure and the transition zone. Furthermore, examinations of the liquid steel refining ability in the considered tundish were carried out. The influence of the filter holes arrangement on the non-metallic inclusions flotation process to the slag phase and liquid steel filtration processes was checked. Numerical simulations were performed in the Ansys-Fluent computer program.

In the presented work, the numerical simulations results of the liquid steel flow in the one strand tundish were shown. Influence of the modification and immersion depth in the liquid steel of the ladle shroud and subflux turbulence controller on hydrodynamic structure of the liquid steel movement in the working space of tundish were examined. The ladle shroud shape modification consisted on the decompression and compression of the main supplying stream of the tundish. The mathematical model used in the numerical simulations through physical modeling and industrial trials were validated. The numerical simulation results (using four variants of the modified ladle shroud immersion depth in the liquid steel) in the isothermal conditions using laboratory experiments on the water model were verified. Whereas, the numerical simulation results (using one of the tundish research variant) for non-isothermal were compared with the results from the industrial measurements. Three turbulence models: Realizable k-ε, RNG k-ε and SST k-ω were used in the computer calculations (performed via the Ansys-Fluent computer program). In order to obtain the actual view of the liquid steel flow hydrodynamic structure in the examined tundish for the two mathematical models using different turbulence models, which were most similar to the laboratory experiments and industrial measurements, the numerical simulations were performed in the non-isothermal conditions. The application in the computer calculations of the SST k-ω turbulence model caused the smallest differences between the numerical simulations, laboratory experiments and industrial measurements. Performed tests showed that ladle shroud can be used as a flow control device and the modified ladle shroud immersion at a depth of 0.1 m in the liquid steel caused the shortest range of the transition zone among the tested cases.

The main purpose of the present work was to validate the numerical model for the pulse-step liquid steel alloying method using a physical simulator that enables the observation and recording of phenomena occurring during the continuous steel casting process. The facility under investigation was a single-nozzle tundish equipped with a dam. To physical trials the glass water model was made on a scale of 2:5. For the mathematical description of turbulence during liquid steel alloying process, the k-ε and k-ω models were employed in the simulations. Based on the computer simulations and physical trials carried out, alloy addition behaviour and mixing curves for different tundish alloy addition feeding positions were obtained. The change in the location of alloy addition feeding to the liquid steel had an effect on the process of alloy addition spread in the liquid steel bulk and on the mixing time.

The tundish prevents unsteady flow affecting on the steel cleanness and temperature. The presented article offers a new design of a ladle shroud (LS) with three holes placed in a special dome (separating the steel flow) steeped in a metal bath. Various options of the LS construction were analysed, as well as its positioning in the tundish in relation to its longitudinal axis. The conducted numerical simulations enabled to assess the impact of the designed ladle shroud on the flow of liquid steel through the tundish. The results showed that the best option is to use the LS with two larger holes and one smaller which activates the flow structure and reduces the rate of the liquid steel velocity in the tundish, limiting the flow turbulence.