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

The Korean Society of Mechanical Engineers (대한기계학회)
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An Experimental Study on the Effects of Concentration Gradient and Mean Velocity on the Liftoff Characteristics of the Triple Flame

농도구배와 평균속도가 삼지화염의 부상 특성에 미치는 영향에 관한 실험적 연구

  • 서정일 (한국과학기술원 기계공학과) ;
  • 김남일 (한국과학기술원 연소기술연구센터) ;
  • 오광철 (한국과학기술원 기계공학과) ;
  • 신현동 (한국과학기술원 기계공학과)
  • Published : 2003.08.01
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Abstract

A triple flame in a mixing layer was studied experimentally with concentration gradient and mean velocity by using a multi-slot burner, which can stabilize the lift-off flame. Flame stabilization condition, lift-off heights, and some other characteristics were examined for methane and propane flame within a range of very low concentration gradient. Pitot-tube and LDV(Laser Doppler Velocimetry) were used for velocity. Mass spectroscopy and Rayleigh scattering signal were used for concentration gradients. Thermo-couples and SiC TFP(Thin Filament Pyrometer) were used for temperature. It was found that minimum values of the lift-off heights exist at a certain concentration gradient for constant mean velocity and this means that the propagation velocity has a maximum value. The scales of flame to the burner nozzle and intensity variation of the diffusion flame were suspected as the cause.

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References

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