Publication detail

Analysis of atypical break out during a radial continuous casting of a slab in the straightening zone I. Numerical simulation of temperature field of a slab

KAVIČKA, F. ŠTĚTINA, J. SEKANINA, B. STRÁNSKÝ, K. DOBROVSKÁ, J. MAUDER, T. MASARIK, M.

Original Title

Analysis of atypical break out during a radial continuous casting of a slab in the straightening zone I. Numerical simulation of temperature field of a slab

English Title

Analysis of atypical break out during a radial continuous casting of a slab in the straightening zone I. Numerical simulation of temperature field of a slab

Type

journal article - other

Language

en

Original Abstract

Original numerical model was applied to the simulation of the transient temperature field of concast steel slab of two different chemical composition. The model solves the Fourier-Kirchhoffs equation of the temperature field of slab- crystallizer system respectively slab-ambient system with these different thermophysical parameters : thermal conductivity, specific heat capacity, density and enthalpy including their dependence on temperature. When both melts follow closely after each other, the critical state of so called break out occurs at a certain point secondary cooling zone of a caster. It is obviously a combination of surface defects. However different chemical composition of two steels and their mixing is apparently decisive. Therefore the temperature model has simulated the temperature history of every point of a cross-section of a slab during its movement through the whole caster from the level of the melt in the crystallizer to the cutting torch for both melts and and for their mixture (with average chemical composition). Calculation of the temperature field of a slab has focused mainly on the part of the slab before the break out and its surroundings. Calculation results were compared graphically by means of a graph of temperatures in characteristic points of the cross section, a graph of isotherms in the critical cross-section passing through the break out including isoliquidus and isosolidus, a graph of isotherms in longitudinal sections and a graph of increase in thickness of a solidified shell. The definition of the boundary conditions for all three variants of calculation are identical in all cooling zones. The results of the temperature field can establish a model of the chemical heterogeneity of steel supported by material expertise on samples taken from the break out.

English abstract

Original numerical model was applied to the simulation of the transient temperature field of concast steel slab of two different chemical composition. The model solves the Fourier-Kirchhoffs equation of the temperature field of slab- crystallizer system respectively slab-ambient system with these different thermophysical parameters : thermal conductivity, specific heat capacity, density and enthalpy including their dependence on temperature. When both melts follow closely after each other, the critical state of so called break out occurs at a certain point secondary cooling zone of a caster. It is obviously a combination of surface defects. However different chemical composition of two steels and their mixing is apparently decisive. Therefore the temperature model has simulated the temperature history of every point of a cross-section of a slab during its movement through the whole caster from the level of the melt in the crystallizer to the cutting torch for both melts and and for their mixture (with average chemical composition). Calculation of the temperature field of a slab has focused mainly on the part of the slab before the break out and its surroundings. Calculation results were compared graphically by means of a graph of temperatures in characteristic points of the cross section, a graph of isotherms in the critical cross-section passing through the break out including isoliquidus and isosolidus, a graph of isotherms in longitudinal sections and a graph of increase in thickness of a solidified shell. The definition of the boundary conditions for all three variants of calculation are identical in all cooling zones. The results of the temperature field can establish a model of the chemical heterogeneity of steel supported by material expertise on samples taken from the break out.

Keywords

Concastslab, steel, chemical composition of steel, thermo-physical properties, temperature field, numerical model, breakout

RIV year

2013

Released

10.04.2013

Pages from

53

Pages to

59

Pages count

7

BibTex


@article{BUT103006,
  author="František {Kavička} and Josef {Štětina} and Bohumil {Sekanina} and Karel {Stránský} and Jana {Dobrovská} and Tomáš {Mauder} and Miloš {Masarik}",
  title="Analysis of atypical break out during a radial continuous casting of a slab in the straightening zone I. Numerical simulation of temperature field of a slab",
  annote="Original numerical model was applied to the simulation of the transient temperature field of concast steel slab of two different chemical composition. The model solves the Fourier-Kirchhoffs equation of the  temperature field of slab- crystallizer system respectively  slab-ambient system   with these  different  thermophysical  parameters : thermal conductivity, specific heat capacity, density and enthalpy including their dependence on temperature. When both melts follow closely after each other, the critical state of so called break out occurs at a certain point secondary cooling zone of a caster. It is obviously a combination of surface defects. However different chemical composition of  two steels and their mixing is apparently decisive. Therefore the temperature model has simulated the temperature history of  every point of a cross-section of a slab  during its movement through the whole caster from the level of the melt in the crystallizer to the cutting torch for both melts and and for their mixture (with average chemical composition). Calculation of the temperature field of a slab has focused mainly on the part of the slab before the break out  and its surroundings. Calculation results were compared graphically by means of a graph of temperatures in  characteristic points of the cross section, a graph of isotherms in the critical cross-section passing through the break out including isoliquidus and isosolidus, a graph of isotherms in longitudinal sections and a graph of increase in thickness of a solidified shell. The definition of the boundary conditions for all three variants of calculation are identical in all cooling zones. The results of the temperature field can establish a model of the chemical heterogeneity of steel supported by material expertise on samples taken from the break out.",
  chapter="103006",
  number="2",
  volume="2013",
  year="2013",
  month="april",
  pages="53--59",
  type="journal article - other"
}