Journal of computational fluids engineering (한국전산유체공학회지)

Korean Society of Computational Fluids Engineering (한국전산유체공학회)
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NUMERICAL ANALYSIS ON THE MIXING OF A PASSIVE SCALAR IN THE TURBULENT FLOW OF A SMALL COMBUSTOR BY USING LARGE EDDY SIMULATION

큰에디모사법을 이용한 소형 연소기의 난류 유동장 내 스칼라 혼합에 대한 수치해석

  • 최항석 (한국기계연구원 청정환경기계연구 센터) ;
  • 박태선 (경북대학교 기계공학부) ;
  • Published : 2006.12.31
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Abstract

The characteristics of turbulent flow and mixing in a small can type combustor are investigated by means of Large Eddy Simulation (LES). Attention is paid for a combustor having a baffle plate with oxidant injection and fuel injection holes and study is made for three cases of different baffle plate configurations. From the result, it is confirmed that mixing is promoted by interaction between the jets during their developing process and large vortical flows generated in the vicinity of the combustor wall or fuel jet front. This particular flow feature is effective to accelerate the slow mixing between fuel and oxidant suffering from low Reynolds number condition in such a small combustor. In particular, the vortical flow region ahead of fuel jet plays an important role for rapid mixing. Discussion is made for the time and space averaged turbulent flow and scalar quantities which show peculiar characteristics corresponding to different vortical flow structures for each baffle plate shapes.

Keywords

References

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