Journal of the Korean Society of Combustion (한국연소학회지)

The Korean Society of Combustion (한국연소학회)
권호 표지

Diffusive-Thermal Instability and Buoyancy-Driven Instability in Laminar Attached Free-jet Flames with DC Electric Fields

직류 전기장을 인가한 층류부착화염에서 물질-열 확산 및 부력에 의한 화염진동 비교에 관한 연구

  • 한종규 (부경대학교 기계공학과) ;
  • 윤성환 (부경대학교 친환경수송시스템연구소) ;
  • 박정 (부경대학교 기계공학과) ;
  • 윤진한 (한국기계연구원 그린환경에너지기계본부) ;
  • 길상인 (한국기계연구원 그린환경에너지기계본부) ;
  • 서상일 (한국전력연구원 수화력발젼팀) ;
  • 김영주 (한국전력연구원 수화력발젼팀)
  • Received : 2011.06.26
  • Accepted : 2011.07.15
  • Published : 2011.09.30
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Abstract

In this paper, we describe the behavior of two self-excitations in laminar attached free-jet flames under the influence of DC electric fields, one of buoyancy-driven and the other of diffusion-thermal instability, established from the horizontal and vertical injection. In the horizontal injection with removed buoyancy effect, oscillating flames with the frequency of 1.3 - 7.4 Hz were observed in a certain condition with Lewis number more than unity. On the other hand, it was appeared Lewis number induced self-excitation as well as buoyancy-driven self-excitation in the vertical upward injection with DC electric fields. This behavior had frequency range of 1.6 - 9.4 Hz and was exhibited to attribute the buoyancy effect. Finally, a well-defined division about two self-excitations having similar frequency range is briefly discussed.

Keywords

References

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