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Basic Experimental Study of the Edge-Flame Intensity Variation at High Temperature and with Small Fuel-Concentration Gradient

고온 미소농도구배 조건에서의 에지화염 강도 변화에 관한 실험적 기초 연구

  • Lee, Min-Jung (School of Mechanical Engineering, Chung Ang Univ.) ;
  • Kim, Nam-Il (School of Mechanical Engineering, Chung Ang Univ.)
  • Received : 2011.02.09
  • Accepted : 2011.03.22
  • Published : 2011.06.01

Abstract

In this study, the stabilization of an edge flame and the intensity variation of a diffusion branch were investigated using a multi-slot combustor under conditions of high temperature and small fuel-concentration gradient (FCG). The combustor consists of three narrow channels: a quartz channel and two side-heating combustors. For the accuracy of this experimental study, quantitative analysis was carried out for each boundary condition. Stable edge flames could be observed under high-temperature conditions by controlling the FCG and fuel dilution ratio. Moreover, it was found that the intensity of the diffusion flame was increased by increasing the temperature of the mixture. On the contrary, the intensity of the diffusion flame was decreased by increasing the dilution ratio. It was also found that a propane flame is more sensitively affected by these experimental parameters than a methane flame.

본 연구에서는 고온의 미소농도구배 조건에서의 에지화염의 안정화 및 화염 강도 변화를 실험적으로 관찰하였다. 실험 연소기는 크게 혼합기가 투입되는 슬롯과 석영 채널 및 채널 내부 가열을 위한 추가적인 예혼합 연소기로 구성되어 있다. 실험의 정확성을 위해 각 경계 조건에 대한 정량적인 검증 절차가 수행되었다. 결론적으로 연료 농도 구배의 정량적인 제어와 질소 희석비율을 조절하여 고온의 조건에서도 에지화염을 임의의 위치에 안정화 시킬 수 있었다. 에지화염 내부에 존재하는 확산화염의 화염 강도가 채널 내부의 온도증가에 따라 증가하고 질소의 희석비율 증가에 따라 감소하는 것을 보였다. 연료에 따른 화염 강도 변화를 살펴본 결과 프로판의 경우가 메탄에 비해 강도 변화율이 큰 것을 알 수 있었다.

Keywords

References

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