Transient Mold Fluid Flow with Well- and Mountain-Bottom Nozzles in Continuous Casting of Steel

Chaudhary, Rajneesh; Lee, Go Gi; Thomas, Brian G.; Kim, Seon Hyo

doi:10.1007/s11663-008-9192-0

Cited by 60 publications

(56 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…8(b). Higher surface velocities are found towards the quarter point, midway between the SEN and the NF, as typical for a doubleroll flow pattern 13,17,35) The highest velocity is found closer to the OR. Surface velocity fluctuations are consistently very large ~0.12 m/sec across the entire mold width.…”

Section: Surface Velocitymentioning

confidence: 81%

“…The strongest fluctuation powers are generally found at the lowest frequencies, which matches previous observations. 35) Strong peaks are observed in the nozzle and mold with various frequencies between 0.1 and 10 Hz, including several characteristic frequencies of 0.5-2 Hz at the nozzle port and jet core, due to the interaction between the strong recirculation in the nozzle bottom and the natural turbulence. These frequency ranges correspond to the time intervals of periodic momentum fluctuations in the mold (0.1 to 10 sec) and in the nozzle (0.5 to 2 sec).…”

Section: Transient Velocity Variationmentioning

confidence: 99%

See 1 more Smart Citation

Transient Fluid Flow during Steady Continuous Casting of Steel Slabs: Part I. Measurements and Modeling of Two-phase Flow

2014

Self Cite

View full text Add to dashboard Cite

Unstable mold flow could induce surface velocity and level fluctuations, and entrain slag, leading to surface defects during continuous casting of steel. Both argon gas injection and Electro-Magnetic Braking (EMBr) greatly affect transient mold flow and stability. Part I of this two-part article investigates transient flow of steel and argon in the nozzle and mold during nominally steady-state casting using both plant measurements and computational modeling. Nail board dipping measurements are employed to quantify transient surface level, surface velocity, flow direction, and slag depth. Transient flow in the nozzle and strand is modeled using Large Eddy Simulation (LES) coupled with the Lagrangian Discrete Phase Model (DPM) for argon gas injection. The surface level of the molten steel fluctuates due to sloshing and shows greater fluctuations near the nozzle. The slag level fluctuates with time according to the lifting force of the molten steel motion below. Surface flow shows a classic double roll pattern with transient cross-flow between the Inside Radius (IR) and the Outside Radius (OR), and varies with fluctuations up to ~50% of the average velocity magnitude. The LES results suggest that these transient phenomena at the surface are induced by up-and-down jet wobbling caused by transient swirl in the slide-gate nozzle. The jet wobbling influences transient argon gas distribution and the location of jet impingement on the Narrow Face (NF), resulting in variations of surface level and velocity. A power-spectrum analysis of the predicted jet velocity revealed strong peaks at several characteristic frequencies from 0.5-2 Hz (0.5-2 sec).

show abstract

Section: Surface Velocitymentioning

confidence: 81%

Section: Transient Velocity Variationmentioning

confidence: 99%

Transient Fluid Flow during Steady Continuous Casting of Steel Slabs: Part I. Measurements and Modeling of Two-phase Flow

2014

Self Cite

View full text Add to dashboard Cite

show abstract

“…[24,25] This unbalanced flow is likely aggravated by the mountain-bottom (pointed-bottom) shape of this nozzle, which creates strong low-frequency fluctuations, relative to well-bottom nozzles. [26] The application of the EMBr field suppresses all the scales of turbulence captured in the current study, from small eddies (<1 mm) to large side- Fig. 7-(a) Power spectrum of V z at P3 in the in the jet region.…”

Section: A Mold Flowmentioning

confidence: 67%

Large Eddy Simulations of Double-Ruler Electromagnetic Field Effect on Transient Flow During Continuous Casting

Singh

Thomas

Vanka

2014

Metall Mater Trans B

View full text Add to dashboard Cite

Transient flow during nominally steady conditions is responsible for many intermittent defects during the continuous casting of steel. The double-ruler electromagnetic field configuration, or ''FC-Mold EMBr,'' is popular in commercial slab casting as it provides independent control of the applied static field near the jet and free surface regions of the mold. In the current study, transient flow in a typical commercial caster is simulated in the absence and in the presence of a double-ruler magnetic field, with rulers of equal strengths. Large eddy simulations with the inhouse code CU-FLOW resolve the important transient behavior, using grids of over five million cells with a fast parallel solver. In the absence of a magnetic field, a double-roll pattern is observed, with transient unbalanced behavior, high surface velocities (~0.5 m/s), surface vortex formation, and very large surface-level fluctuations (~±12 mm). Applying the magnetic field suppresses the unbalanced behavior, producing a more complex mold flow pattern, but with much lower surface velocities (~0.1 m/s), and a flat surface level with small level fluctuations (<±1 mm). Nail board measurements taken at this commercial caster, in the absence of the field, matched reasonably well with the calculated results, both quantitatively and qualitatively.

show abstract

“…2008 [20] than well-shaped bottom SEN. [21,22] Ismael VOF Standard k-ε -Effect of deviation of the nozzle towards the inner mold radius on the symmetrical flow pattern and better meniscus control.…”

Section: Introductionmentioning

confidence: 94%

“…Therefore, in order to understand the steel CCC process of round billets, mathematical modeling of the fluid flow phenomena is a feasible choice. Many turbulent models and multiphase models have been used for the fluid flow in gas-stirred steel refining processes [10][11][12] and steel continuous casting processes [13][14][15][16][17][18][19][20][21][22][23] , as summarized in Table I. However, so far very few investigations on CCC process were reported.…”

Section: Introductionmentioning

confidence: 99%

Modeling on Fluid Flow and Inclusion Motion in Centrifugal Continuous Casting Strands

Wang

Zhang

Sridhar

2016

Metall Mater Trans B

View full text Add to dashboard Cite

In the current study, a three-dimensional multi-phase turbulent model was established to study the transport phenomena during centrifugal continuous casting process. The to 18° and rotation speed from 40 to 80 revolutions per minute favored to decrease the total volume of entrained bubbles, while the increase of distance of nozzle moving left and casting speed had reverse effects. The trajectories of inclusions in the mold were irregular, and then rotated along the strand length. After penetrating a certain distance, the inclusions gradually moved to the center of billet and gathered there. To discuss the heat transfer, solidification and inclusions entrapment during centrifugal continuous casting, more work will be performed.

show abstract

Transient Mold Fluid Flow with Well- and Mountain-Bottom Nozzles in Continuous Casting of Steel

Cited by 60 publications

References 20 publications

Transient Fluid Flow during Steady Continuous Casting of Steel Slabs: Part I. Measurements and Modeling of Two-phase Flow

Transient Fluid Flow during Steady Continuous Casting of Steel Slabs: Part I. Measurements and Modeling of Two-phase Flow

Large Eddy Simulations of Double-Ruler Electromagnetic Field Effect on Transient Flow During Continuous Casting

Modeling on Fluid Flow and Inclusion Motion in Centrifugal Continuous Casting Strands

Contact Info

Product

Resources

About