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

The Korean Society of Mechanical Engineers (대한기계학회)
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Analysis of a Vortex Structure Near the Strip Edge for Preventing Edge Zn Overcoation

단부 아연 과도금 방지를 위한 단부 와동 구조의 분석

  • 조중원 (한국과학기술원 기계공학과) ;
  • 김상준 (포항산업과학연구원 설비.자동화연구센터) ;
  • 안기장 (한국과학기술원 기계공학과) ;
  • 정명균 (한국과학기술원 기계공학과)
  • Published : 2003.08.01
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Abstract

In the gas wiping process of continuous hot-dip galvanizing, edge overcoating develops near the edge of the steel strip. The overcoating is supposed to occur due to the reduced impact pressure of wiping gas on the strip surface. The purpose of this study is to investigate the effect of edge vortex on the reduced impact pressure. Three-dimensional unsteady flows are simulated using a commercial code, STAR-CD. Standard k-$\varepsilon$ model is used as a turbulence model. It is found that an alternating vortex structure in the vicinity of strip edge is developed by buckling of opposed jet streams and that the reduced amount of impact pressure at strip edge becomes smaller as the air knife gets closer to the strip. The effect of edge baffle on the reduced impact pressure is also investigated.

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References

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