Optimization of Pulse-Step Method for Liquid Steel Alloying in One Strand Slab Tundish

2018 ◽  
Vol 941 ◽  
pp. 58-63 ◽  
Author(s):  
Adam Cwudziński
Keyword(s):  
Liquid Steel ◽  
Continuous Casting Machine ◽  
Casting Machine ◽  
Computational Grids ◽  
Time Interval ◽  
Step Method ◽  
Ansys Fluent ◽  
Pulse Charge ◽  
Steel Alloying ◽  
Steel Flow

Introduction to the Fe-C-X system: Si, Mn, Al and Nb, Ti, V, B allow the ultimate tensile strength and ductility of steel to be increased at the same time. Therefore, multiphase steels of the TRIP, DP, MART and CP are the steels of the future. The scientific aim of the researches were to obtain new basic information on alloying process of liquid steel in a tundish with the use of the pulse–step method. The facility under investigation was a single outlet tundish being a component of a slab continuous casting machine. Computer simulations of the liquid steel flow and alloy behaviour in turbulent motion conditions were done using the Ansys-Fluent computer program. For generating the computational grids, Gambit program was used. For pulse–step method optimisation two aspects were considered. At first numerical simulations were performed for the selection of the time interval between the pulse feed of the first alloy batch and the continuous feed of subsequent alloy batches in order to maintain the required homogenisation level. Next simulations were done for determination of the mass of the pulse charge that ensures not only the attainment of the 95% homogenisation level, but also the limitation of alloy concentration peaks occurring in the liquid steel and going beyond the 95% homogenisation zone. On the basis of numerical investigations the mixing curves and time mixing for different variants of pulse-step method optimization were obtained.

scholarly journals Effect Of Steel Flow Control Devices On Flow And Temperature Field In The Tundish Of Continuous Casting Machine

2015 ◽  
Vol 60 (2) ◽  
pp. 843-847 ◽  
Author(s):  
L. Sowa
Keyword(s):  
Mathematical Model ◽  
Flow Control ◽  
Numerical Simulations ◽  
Liquid Steel ◽  
Continuous Casting Machine ◽  
Casting Machine ◽  
Flow Control Devices ◽  
Control Devices ◽  
Steel Flow ◽  
The Mathematical Model

AbstractThe mathematical model and numerical simulations of the liquid steel flow in a tundish are presented in this paper. The problem was treated as a complex and solved by the finite element method. One takes into consideration in the mathematical model the changes of thermophysical parameters depending on the temperature. The single-strand tundish is used to casting slabs. The internal work space of the tundish was modified by flow control devices. The first device was a pour pad situated in the pouring tundish zone. The second device was a dam. The third device was a baffle with three holes. The dam and baffle were placed in the tundish at different positions depending on the variant. The main purpose of using these was to put barriers in the steel flow path as well as give directional metal flow upwards which facilitated inclusion floatation. The interaction of flow control devices on hydrodynamic conditions was received from numerical simulations. As a result of the computations carried out, the liquid steel flow and steel temperature fields were obtained. The influences of the tundish modifications on the velocity fields in liquid phase of the steel were estimated, because these have essential an influence on high-quality of a continuous steel cast slab.

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

2016 ◽  
Vol 61 (1) ◽  
pp. 295-300 ◽  
Author(s):  
A. Cwudziński
Keyword(s):  
Liquid Steel ◽  
Mixing Time ◽  
Hydrodynamic Conditions ◽  
Step Method ◽  
Ansys Fluent ◽  
Working Space ◽  
Alloy Addition ◽  
Steel Flow ◽  
Mixing Curves ◽  
Active Flow

The knowledge of the hydrodynamic pattern aids in designing new and modernizing existing tundishes. The device under examination is an one-strand tundish of a capacity of 30 Mg. Computer simulation of the liquid steel flow, tracer and alloy addition behaviour in turbulent motion conditions was done using the Ansys-Fluent®computer program. The hydrodynamic conditions of steel flow were determined based on the distribution of the characteristics of tundish liquid steel residence time distribution (RTD). The alloy addition was introduced to the liquid steel by the pulse-step method. Based on computer simulations carried out, steel flow fields and RTD and mixing curves were obtained, and the shares of stagnant volume flow and active flow and the mixing time were computed. Dispersion of the alloy addition in liquid steel during its flow through the tundish is a dynamic process which is determined by the hydrodynamic conditions occurring in the tundish working space.

scholarly journals New Insight on Liquid Steel Microalloying by Pulse-Step Method in Two-Strand Slab Tundish by Numerical Simulations

Crystals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 448
Author(s):  
Adam Cwudziński
Keyword(s):  
Liquid Steel ◽  
Mixing Time ◽  
Casting Process ◽  
Step Method ◽  
Flow Control Devices ◽  
Alloy Addition ◽  
Interesting Approach ◽  
Control Devices ◽  
Steel Flow ◽  
Alloy Concentration

Developing a technology for introducing alloy addition to liquid steel during the course of continuous casting process seems to be an interesting approach to enhancing the steelmaking process, especially as the effective introduction of micro-additives or non-metallic inclusion modifiers to the liquid steel is the key to the production of the highest-quality steel. This paper presents the results of investigation describing the process of liquid steel chemical homogenisation in the two-strand slab tundish. The alloy was fed to liquid steel by pulse-step method. Five tundish equipment variants with different flow control devices and alloy addition feeding positions were considered. The paper includes fields of liquid steel flow, alloy concentration vs. time curves, dimensionless mixing time, minimum time values and alloy concentration deviations at tundish outlets. The results pointed much more effectively with liquid steel mixing nickel than aluminium. For aluminium obtaining a 95% chemical homogenisation level requires three-fold more time. Moreover, it is definitely beneficial for chemical homogenisation to initiate the alloying process simultaneously in two sites. This procedure generates, among others, the least alloy deviation of concentration at tundish outlets.

Designing of a Novel Shroud for Improving the Quality of Steel in Tundish

2012 ◽  
Vol 585 ◽  
pp. 359-363 ◽  
Author(s):  
Debasish Chatterjee
Keyword(s):  
Continuous Casting ◽  
Continuous Casting Machine ◽  
Casting Machine ◽  
Steel Production ◽  
Metal Bath ◽  
Ladle Slag ◽  
Exchange Operation ◽  
Slag Entrainment ◽  
Steel Flow

In present 92.8% of world steel production is casted on continuous casting machine. The key phase of continuous casting is tundish. Beside of refining effect of slag phase also steel flow in tundish is very important factor. The main causes for inclusion formation and contamination of the melt include reoxidation of the melt by air and carried over oxidizing ladle slag, entrainment of tundish and ladle slag, and emulsification of these slags into the melt. These causes are due to generation of turbulence in the melt. Although turbo stop lowers the turbulence in some extent. But it is not capable of totally decrease of turbulence specially during lowering of metal bath at the time of ladle exchange operation, cause contamination of the steel melt in tundish. So in the present work it has been focused to develop a novel shroud which have significant role to supply of steel from ladle to tundish at slow rate to avoid turbulence, emulsification and formation of slag eye in tundish to produce quality steel in a sustained manner.

Mathematical Modeling and Industrial Experiment of Liquid Steel Flow in the Three Outlets Continuous Casting Bloom Tundish

2013 ◽  
Vol 58 (4) ◽  
pp. 1077-1083 ◽  
Author(s):  
A. Cwudzinśki
Keyword(s):  
Liquid Steel ◽  
Mass Scale ◽  
Correct Process ◽  
Ansys Fluent ◽  
Industrial Experiment ◽  
Flow Control Devices ◽  
Working Volume ◽  
The Subject ◽  
Control Devices ◽  
Steel Flow

Abstract The dynamic development of the continuous steel casting (CSC) process has resulted in the application of this technology to the casting of steel semi-finished products on a mass scale. In the CSC process, before the cooling and solidification of liquid steel commences, the liquid metal dynamically flows through the steelmaking ladle, the tundish and the mould. Therefore, the control of steel flow is the key to the correct process. One of the metallurgical device in which the control of steel flow hydrodynamics is of crucial importance is the tundish. The subject of investigation within the present study was a three-nozzle tundish designed for casting of blooms. The software program Ansys-Fluent R was employed for the analysis of tundish operation. For the verification of the correctness of obtained results, an industrial experiment was carried out. For modification of the hydrodynamic conditions within the working volume of the tundish, two flow control devices were proposed, namely: a dam and a dam with an overflow window. The outcome of performed computer simulations were liquid steel flow fields and residence time distribution curves.

Numerical Modeling of Nonmetallic Inclusions Flowing Out during Solidification of Continuous Cast Steel Billets in Mould Zone

2012 ◽  
Vol 706-709 ◽  
pp. 1385-1390 ◽  
Author(s):  
Wlodzimierz Derda ◽  
Ireneusz Staniewski
Keyword(s):  
Liquid Steel ◽  
Cast Steel ◽  
Continuous Casting Machine ◽  
Casting Machine ◽  
Continuous Cast ◽  
Metallic Inclusions ◽  
Different Types ◽  
Metal Volume ◽  
Steel Grades ◽  
Continuous Cast Steel

Developing the metallurgical purity of steel products requires, among other things, the understanding of the behavior of non-metallic inclusions (NMI) in the bulk of liquid steel in the mould zone within the forming skin of a concast billet. The identification of the mode of NMI distribution with different values of casting parameters influencing the state of the metal in the mould, including electromagnetic stirring intensity, may be of key importance to developing the metallurgical purity of concast billets being cast. The present article discusses the analysis of the results of simulation of NMI flowing out from the liquid steel volume in the mould zone of the steel continuous casting machine (CCM). As the investigation object, two different types of square cross-section mould were chosen, while for carrying out computations for two selected steel grades, a hydrodynamic module (HDM) being an extension of the FLUENT® program was employed. The use of this module made it possible to take consideration of the influence of the EMS-M type electromagnetic stirrer on the conditions of NMI flotation and distribution in the metal volume within the mould for defined thermal – dynamical conditions.

scholarly journals Piv Method and Numerical Computation for Prediction of Liquid Steel Flow Structure in Tundish

2015 ◽  
Vol 60 (1) ◽  
pp. 11-17 ◽  
Author(s):  
A. Cwudziński
Keyword(s):  
Computer Simulations ◽  
Liquid Steel ◽  
Laboratory Experiments ◽  
Field Analysis ◽  
Ansys Fluent ◽  
Measuring Systems ◽  
Piv Method ◽  
Commercial Program ◽  
Flow Field Analysis ◽  
Steel Flow

AbstractThis paper presents the results of computer simulations and laboratory experiments carried out to describe the motion of steel flow in the tundish. The facility under investigation is a single-nozzle tundish designed for casting concast slabs. 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. State-of-the-art vector flow field analysis measuring systems developed by Lavision were used in the laboratory tests. Computer simulations of liquid steel flow were performed using the commercial program Ansys-Fluent¯. 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.

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