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OH, PAHs and Soot Ditribution in a Laminar Diffusion Flame Under Oxidizer Deficient Ambience

산화제 결핍 분위기에서의 층류 확산화염내 OH, PAHs 및 그을음 분포

  • 심성훈 (한국기계연구원 열유체환경연구부) ;
  • 신현동 (한국과학기술원 기계공학과)
  • Published : 2002.10.01

Abstract

We investigate the flame behavior and spatial distribution of OH, PAHs and soot in a confined buoyant diffusion flame with decrease of the coflowing air flow rate. Direct photographs and Schlieren images represent that flame is Ally occupied by blue flame and becomes unstable, which is partially detached to the fuel nozzle tip in a near extinction flame under extremely reduced oxidizer condition. Laser induced fluorescence profiles clearly shows that OH is still generated in near-extinction flame, although intensity becomes weak with decreasing air flow rate. But soot scattering image cannot be seen any more in an oxidizer deficient ambience and simultaneously the PAHs are widely distributed downstream. These results are due to that a decrease of oxygen concentration in the combustion chamber leads to a temperature drop of flame, as a consequence, to a delay in soot growth and to a expanding of the PAHs, as soot precursors.

Keywords

References

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