Multiphase Numerical Model of Molten Steel and Slag Behavior in the Continuous Casting Mould

Abstract

The paper reports the results of numerical simulation of the flow of liquid steel with the use of a multiphase model. The facility under study was a mould designed for continuous casting of steel slabs. The geometry of the facility, along with the computational grid, was generated within the program Ansys-Meshing R . Numerical computations were performed in the programs: COMSOL Multiphysics R and Ansys-Fluent R . The use of the multiphase model enabled the determination of the behavior of the liquid slag layer on the metal bath surface. From the performed computer simulations, the fields of liquid steel motion and liquid steel turbulence kinetic energy distribution in the mould's symmetry plane have been presented. Based on the values recorded at selected measurement points located on the slag surface, a diagram illustrating the variation of the slag layer position during continuous steel casting has been plotted.Keywords:continuous casting mould, liquid steel, slag, multiphase fluid flow model W niniejszej pracy przedstawiono wyniki symulacji numerycznej przepływu ciekłej stali z wykorzystaniem modelu wielofazowego. Badanym obiektem był krystalizator przeznaczony do ciągłego odlewania stalowych wlewków płaskich. Geometrię obiektu wraz z siatkę obliczeniową wygenerowano w programie Ansys-Meshing R . Obliczenia numeryczne wykonano w programach: COMSOL Multiphysics R i Ansys-Fluent R . Zastosowanie modelu wielofazowego pozwoliło na określenie zachowania się warstwy ciekłego żużla na powierzchni kąpieli metalowej. Na podstawie wykonanych symulacji komputerowych zaprezentowano pola ruchu ciekłej stali oraz rozkładu kinetycznej energii turbulencji ciekłej stali w płaszczyźnie symetrii krystalizatora. Bazując na wartościach zarejestrowanych w wybranych punktach pomiarowych, znajdujących się na powierzchni żużla, sporządzono wykres obrazujący zmianę położenia warstwy żużla podczas ciągłego odlewania stali.

Physical Modeling of Mold Slag Entrainment in Continuous Steel Casting Mold with Consideration the Impact of Mold Powder Layer

“…Therefore, the mold slag entrainment is the object of interest for scientists around the world. Research in‐plant are difficult to perform (high temperature, lack of phases and equipment transparency), however they can be successfully modeled using computational fluid dynamics and experiments based on water models …”

“…Therefore, the mold slag entrainment is the object of interest for scientists around the world. Research inplant are difficult to perform (high temperature, lack of phases and equipment transparency), however they can be successfully modeled using computational fluid dynamics [17][18][19] and experiments based on water models. [20][21][22][23][24] Many researchers investigated the mold slag entrainment using a simplified physical models, covering only the upper area of mold.…”

Two-phase analysis of interface level fluctuation in continuous casting mold with electromagnetic stirring

“…Mold flux has a significant role in an unsullied and smooth running of the process (Nowak et al, 2003). The main role of the mold flux powder is to avoid excessive heat removal and re-oxidation of molten steel from meniscus surface, to absorb impurities and non-metallic inclusions and provide lubrication between the solidifying shell and mold wall (Bielnicki et al, 2015;Mcdavid and Thomas, 1996;Yoon et al, 2015). High turbulence near the meniscus causes steel-flux interface fluctuation or frequently called mold level fluctuation (MLF), which may lead to entrapment of mold flux into the liquid steel pool.…”

“…However, application of in-mold electromagnetic stirring (M-EMS) in billet/bloom mold increases the turbulence intensity, which increases the level of fluctuation at the meniscus. Using multiphase model, Bielnicki et al (2015) investigated the molten steel/slag behavior in a slab caster mold having bifurcated nozzle. Authors have predicted the maximum liquid slag level near the narrow mold wall and least at the vicinity of SEN. Zare et al (2013) predicted the interface fluctuation in a thin slab mold with the tetrafurcated nozzle and optimized the casting speed and nozzle submergence depth using height to wavelength criteria.…”

Influence of Continuous Steel Casting Conditions on Behavior and Stability of Liquid Mold Slag During Slab Casting – Physical Modeling

“…However, because of the high temperatures and lack of transparency of the phases (liquid steel, liquid slag) and equipment, the direct observation of liquid slag behavior and its stability in the industrial CSC process is impossible. For this reason, alternative methods have been developed to study the impact of casting conditions on the stability of the liquid mold slag phase, which include mathematical [9,10] and physical modeling [11][12][13].…”