Transactions of the Korean Society of Mechanical Engineers B (대한기계학회논문집B)

The Korean Society of Mechanical Engineers (대한기계학회)
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Analysis of Edge Overcoating in Continuous Hot-Dip Galvanizing

연속식 용용아연도금 공정에서의 단부 과도금 현상에 대한 수치 해석

  • 안기장 (한국과학기술원 기계공학과) ;
  • 김상준 (포스코기술연구소 광양공정제어연구팀) ;
  • 조중원 (한국과학기술원 기계공학과) ;
  • 정명균 (한국과학기술원 기계공학과)
  • Published : 2004.07.01
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Abstract

The problem of edge overcoating developed near the edge of the steel strip is studied quantitatively in the gas wiping process of continuous hot-dip galvanizing. It has been assumed that the edge overcoating occurs due to the reduced impact pressure of wiping gas on the strip edge and it is one of detrimental problems to the quality of coating products. In order to analyse the edge overcoating problem numerically, three-dimensional unsteady flows due to the gas wiping are calculated by using a commercial code, STAR-CD. Standard $\kappa$-$\varepsilon$ model is used as a turbulence model. The 1D code for calculation of coating thickness is constructed by using continuity and Navier-Stokes equations. The calculation results have shown good agreement with measurements of edge overcoating thickness, taken from galvanizing line trials. Therefore it is conformed that the major cause of edge overcoating is the reduced impact pressure of wiping gas on the strip surface.

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References

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