Modelling the influence of changing constructive parameters of multi-strand tundish on steel flow and heat transfer

Abstract

The results of numerical simulation and industrial experiments on thermal and flow phenomena in a multi-strand tundish are presented before and after modernisation. The improvement of cast steel purity and the increase of continuous casting (CC) machine capacity was the basic aim of the research. The simplest action was to increase the height of the tundish side walls, so the working zone of tundish had a higher capacity and inside the working area a turbulence inhibitor was installed. Experimental measurements and numerical calculations enabled to estimate the steel velocity and temperature fields. The research focused on the determination of characteristics residence time distribution. Basing on them, the percentage volume of different flows (dead, dispersed plug, well-mixed) was calculated before and after modernisation, which enabled to evaluate the tundish working conditions. Additionally, they gave information about the influence of the multi-strand constructive changes on the hydrodynamics and thermal conditions.

Archives of Metallurgy and Materials

“…σ T = T liquid = P hydrostatic pressure (8) Where σ T = T liquid is the true stress when the temperatures is higher than the ZST (MPa); P hydrostatic pressure is the ferrostatic pressure acts on the interface between liquid and solidifying shell when the temperatures exceeding ZST (MPa). When the temperature of billet is above ZST and exceeding liquidus of steel, the flow stress can be obtained from the following eq.…”

“…Numerical simulations method has been widely used to analyze and optimize the casting process [5][6][7][8][9]. Many researchers [10,11] have investigated the stress and strain in as-cast billets, to estimate the cracking tendency under the soft reduction process.…”

Effects of Salt Tracer Volume and Concentration on Residence Time Distribution Curves for Characterization of Liquid Steel Behavior in Metallurgical Tundish

“…In the textbook [15] and the past references [16,17], the RTD curves obtained by water model and numerical simulation usually have a single flat peak, single sharp peak or double peaks [18][19][20][21]. Maybe these three types of peaks have some relations with each other.…”

Effect of emptying time on multiphase and mixing behaviours during grade change of a five-strand bloom tundish

“…Recently, with the increase of steel grades and the improvement of CC efficiency requirements, casting with different steel grades has become a main component of steelmaking plants. Much of the research focuses on numerical and physical analyses of the mixing process of molten steel during steady-state casting [3][4][5][6][7][8][9]. Merder et al [3] discussed the thermal and flow phenomena in a multi-strand tundish before and after modernization, found that the modernization is favourable in the aspect of transient zone during the sequence casting of different grades of steel.…”

“…Much of the research focuses on numerical and physical analyses of the mixing process of molten steel during steady-state casting [3][4][5][6][7][8][9]. Merder et al [3] discussed the thermal and flow phenomena in a multi-strand tundish before and after modernization, found that the modernization is favourable in the aspect of transient zone during the sequence casting of different grades of steel. Cwudziński et al [5] investigated liquid steel alloying process in one strand tundish, found that the species model can render the macroscopic mixing process occurring in the real metallurgical.…”