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

  • 제26권12호
  • /
  • Pages.1674-1680
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  • 2002
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  • 1226-4881(pISSN)
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  • 2288-5324(eISSN)
대한기계학회 (The Korean Society of Mechanical Engineers)
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후향계단 난류 박리재부착 유동에서의 대형와의 구조

Large-Scale Vertical Structure in Separated and Reattaching Turbulent flow over a Backward Facing Step

  • 안승광 (한국과학기술원 기계공학과) ;
  • 이인원 (LG전자 디지털어플라이언스 연구소) ;
  • 성형진 (한국과학기술원 기계공학과)
  • 발행 : 2002.12.01
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초록

An experimental study was made of a large-scale vortical structure over a backward-facing step. The Reynolds number based on the step height was R $e_{H}$ =33,000. To recognize the large-scale vortex, three components of velocity were measured. The measurements were performed in the recirculation zone (x/H=4.0) and the reattachment zone(x/H=7.5). To measure the wall pressure fluctuations in a turbulent flow over a backward-facing step, a 32-channel microphone array was installed beneath the wall in the streamwise and spanwise directions. From the measured pressure field, the size of large-scale vortex was obtained. As a detailed study, a conditionally-averaging technique was employed to characterize the coherent structure of the large-scale vortex. To see the relationship between the flow field and the relevant spatial mode of the pressure field, the spatial box filtering (SBF) was examined. A cross-correlation between velocity and pressure fluctuations was performed to identify the structure and the length scale of the large-scale vortex.x.

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참고문헌

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