강제 대류하에서 일차원 액적 배열내의 화염 퍼짐에 관한 실험적 연구

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박정;이기만;신강숭
Park, Jeong;Lee, Kiman;Niioka, Takashi

  • 발행 : 2000.01.01

초록

Experimental investigation on flame spread along suspended droplet arrays have been conducted with various droplet spacings and ambient air velocities. Especially, an opposed air stream is introduced to simulate fundamental flame spread behaviors in spray combustion. High-speed chemiluminescence imaging technique of OH radicals has been adopted to measure flame spread rates and to observe various flame spread behaviors. The fuel used is n-Decane and the air velocity varies from 0 to 17cm/s. The pattern of flame spread is grouped into two: a continuous mode and an intermittent one. It is found that there exists droplet spcings, above which flame spread does not occur. The increase of ambient air velocity causes the limit droplet spacing of flame spread to become small due to the increase of apparent flame stretch. As the ambient air velocity decreases, flame spread rate increases and then decreases after taking a maximum flame spread rate. This suggests that there exists a moderate air flowing to give a maximum flame spread rate due to enhanced chemical reaction by the increase of oxidizer concentration.

키워드

화염 퍼짐률;주위 공기 속도;액적 간격;연속적 모드;간헐적 모드

참고문헌

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