Journal of the Korean Society of Combustion (한국연소학회지)

The Korean Society of Combustion (한국연소학회)
권호 표지

Experimental Study on the Edge Flame Stabilization and its Structure Nearby Quenching Limits in a High Temperature Channel

고온 채널 내부 에지화염의 소염 한계 영역에서의 화염 안정화 및 구조에 관한 실험적 연구

  • 이민정 (중앙대학교 기계공학부 대학원) ;
  • 김남일 (중앙대학교 기계공학부)
  • Received : 2010.03.03
  • Accepted : 2010.07.22
  • Published : 2010.09.30
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Abstract

Edge flames have been interested as a basic structure that is concerned to flame stabilization and re-ignition of non-premixed flames. The edge flame consists of a lean premixed flame, a rich premixed flame, and a diffusion flame. In order to investigate fundamental structures of the edge flames at the conditions near the flammability limits, edge flames were stabilized within a heated narrow channel. Highly diluted partially premixed methane was used, and the flow rates of air and the partially premixed mixture were controlled. Various flame behaviors, including a transition between ordinary edge flames and premixed flames, were observed. Flame stabilization characteristics were examined as well. All flame stabilization conditions in this study showed a similar trend: characteristic time scales were inversely proportional to the equivalence ratio defined at the burner inlet. Finally, an interesting flame structure having a weak diffusion branch enveloped by a closed premixed branch was found near the flammability limits even in a fuel-air mixing layer. This structure was named as a "flame-drop" and the importance of this structure was first suggested.

Keywords

References

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