• 한국자동차공학회논문집
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• 제2권4호
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• pp.91-99
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• 1994

Tunable KrF Excimer Laser is used here for measuring OH and $O_2$ density distribustion in an open $H_2$/air premixed flame and in a combustion bomb. Laser Rayleigh Scattering(LRS) and Planar Laser Induced Predissociative Fluorescence(PLIPF) methods are used to obtain two-dimensional images of total and specific densities. Laser Excitation wavelengths are calibrated via flame images and combustion bomb images show good qualitative a greement with theoretical calculation. Furthermore images in a combustion bomb can be developed to study real Spark-Ignition engine combustions. Our experimental images show that there are no more collisional quenching problem at high pressure environment(including atmospheric pressure) using predissociative fluorescence technique. Further development to obtain two-dimensional temperature dustribution is ready to use eventhough it is not reported in this paper.

• 한국연소학회:학술대회논문집
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• 한국연소학회 제26회 KOSCO SYMPOSIUM 논문집
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• pp.137-142
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• 2003

In order to investigate the effect of fuel mixing on PAH and soot formation, four species of methane, ethane, propane and propene have been mixed in counterlfow ethylene diffusion flame. Laser-induced incandescene and laser-induced fluorescene techniques were employed to measure soot volume fraction and polycyclic aromatic hydrocarbon (PAH) concentration, respectively. Results showed that the mixing of ethane (or propane) in ethylene diffusion flame produces more PAHs and soot than those of propene, even though the propene diffusion flame produces more PAHs and soot than that of propane and ethane. Considering that propene directly dehydrogenates to propargyl radical, this behavior implied that the enhancement of PAH and soot formation by the fuel mixing of ethylene and ethane (or propane) cannot be explained by propargyl radical directly dehydrogenated from ethane (or propane).

• 대한기계학회논문집B
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• 제26권6호
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• pp.817-822
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• 2002

Sooting characteristics of counterflow ethylene/propane mixture flames have been experimentally studied to investigate the fuel structure effect on PHM and soot formation. Laser-induced incandescene and laser-induced fluorescene techniques were employed to measure soot volume fraction and polycyclic aromatic hydrocarbon (PAH) concentration, respectively. Importance of $C_{3-}$species on PAH growth as well as the H-abstraction-C$_2$ $H_2$addition (HACA) mechanism has been emphasized, considering that PAH growth rate is greater for with mixed fuel than fer pure fuel flames. It was also confirmed that HACA pathways are the dominant soot growth mechanism. A new PAH growth model including both $C_{2-}$ and $C_{3-}$growth mechanisms is proposed based on the experimental results.

• 한국연소학회지
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• 제8권3호
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• pp.8-14
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• 2003

In order to investigate the effect of fuel mixing on PAH and soot formation, four species of methane, ethane, propane and propene have been mixed in counterlfow ethylene diffusion flame. Laser-induced incandescene and laser-induced fluorescene techniques were employed to measure soot volume fraction and polycyclic aromatic hydrocarbon (PAH) concentration, respectively. Results showed that the mixing of ethane (or propane) in ethylene diffusion flame produces more PAHs and soot than those of propene. Considering that propene directly dehydrogenates to propargyl radical, this behavior implied that the enhancement of PAH and soot formation by the fuel mixing of ethylene and ethane (or propane) cannot be explained solely by propargyl radical directly dehydrogenated from ethane (or propane). Thus, combination reactions between C1 and C2-species for the formation of propargyl was suggested to identify the synergistic effect occurring in the flames of ethylene and propane (or ethane) mixtures.

• 해양환경안전학회지
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• 제18권1호
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• pp.55-60
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• 2012

매연과 다중고리 방향족 탄화수소의 생성에 대하여 n-헵탄의 혼합의 영향을 알아보기 위하여 순수에틸렌 대향류 확산화염에 n-헵탄을 소량 혼합하여 실험을 수행하였다. 매연체적분율과 PAH의 생성 계측에서는 레이저 유도 형광법 (laser-induced fluorescence; LIF)과 레이저 유도 백열법(laser-induced incandescence; LII)의 레이저 계측법을 이용하였다. 실험결과로 순수 에틸렌 화염에 소량의 n-헵탄을 혼합한 경우에는 매연과 다중고리 방향족 탄화수소가 상승하였다. 그러나 20% n-헵탄 혼합화염의 경우 LIF 신호가 감소하였다. 소량의 혼합화염의 경우, 다중고리 방향족 탄화수소와 매연의 상승은 n-헵탄 혼합에 의해 저온 영역에서의 메틸 라디칼의 증가로 의한다고 사료된다. 10% n-헵탄 혼합화염에 대한 화학반응 프로세스를 살펴본 결과 H 라디칼에 의한 반응율이 벤젠 생성에 결정적인 역할을 한다는 것을 알 수 있었다.