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

The Korean Society of Mechanical Engineers (대한기계학회)
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Numerical Study of Density-stratified Flow Past Two 3D Hills - Aligned in Tandem -

두 개의 3차원 지형물 주위의 성층 유동 해석 - 주 유동방향으로 정렬된 경우 -

  • 최춘범 (인하대학교 대학원 기계공학과) ;
  • 양경수 (인하대학교 기계공학부)
  • Published : 2006.12.01
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Abstract

In this paper a parametric study using an immersed boundary method has been carried out to investigate the effects of stable density stratification on the wakes past two identical three-dimensional hills aligned in tandem. The Reynolds number based on the uniform inlet velocity and twice the hill height was fixed at Re=300 while the Froude number based on the inlet velocity and the hill height was retained at Fr=0.2. Neutral flow without density stratification was also computed for comparison. Under a strong stratification, vertical motion of fluid particles over the three-dimensional hills is suppressed and the wake structures behind the hills become planar. Depending on the distance between the two hills, the flow pattern of each wake is significantly affected by the stratification. There is a critical hill distance at which flow characteristics drastically change. Qualitative and quantitative features of the wake interaction are reported.

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References

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