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

The Korean Society of Mechanical Engineers (대한기계학회)
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Numerical Study for Effects of Density-Stratification on Wake Behind a Sphere

구 후류에 미치는 유동장 밀도 성층화 영향 전산 해석

  • 이승수 (충북대학교 구조시스템공학과) ;
  • 양경수 (인하대학교 기계공학과) ;
  • 박찬욱 (대불대학교 기계공학과)
  • Published : 2004.05.01
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Abstract

Stratified flow past a three-dimensional obstacle such as a sphere has been a long-lasting subject of geophysical, environmental and engineering fluid dynamics. In order to investigate the effect of the stratification on the near wake, in particular, the unsteady vortex formation behind a sphere, numerical simulations of stratified flows past a sphere are conducted. The time-dependent Navier-Stokes equations are solved using a three-dimensional finite element method and a modified explicit time integration scheme. Laminar flow regime is considered, and linear stratification of density is assumed under Bossiness approximation. The computed results include the characteristics of the near wake and the unsteady vortex shedding. With a strong stratification, the separation on the sphere is suppressed and the wake structure behind the sphere becomes planar, resembling that behind a vertical cylinder.

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References

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