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Flow Analysis on Near Field of Elliptic Jet Using a Single-Frame PIV

고해상도 PIV 기법을 이용한 타원형 제트의 근접 유동장 해석

  • 신대식 (포항공과대학교 기계공학과) ;
  • 이상준 (포항공과대학교 기계공학과)
  • Published : 2000.03.01

Abstract

Flow characteristics of turbulent elliptic jets were experimentally investigated using a single-frame PIV system. A sharp-edged elliptic nozzle with aspect ratio(AR) of 2 was tested and the experimental results were compared with those of circular jet having the same equivalent diameter($D_e$). The Reynolds number based on the nozzle exit velocity and nozzle equivalent diameter was about $1{\times}10^4$. The spreading rate along the major and minor axis are different remarkably. The jet half width along the major axis decreases at first and then increases with going downstream. But along the minor axis the jet width increases steadily. The elliptic jet of AR=2 has one switching points at $X/D_e=2$ within the near field. Turbulence properties are also found to be significantly different along the major and minor axis planes.

Keywords

References

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