DOI QR코드

DOI QR Code

A Study on Effect of n-heptane Mixing on PAH and Soot Formation in Counterflow Ethylene Diffusion Flames

대향류 에틸렌 확산화염내 PAH 및 매연의 생성에 미치는 n-헵탄 혼합의 영향에 관한 연구

  • Choi, Jae-Hyuk (Division of Marine System Engineering Korea Maritime University) ;
  • Han, Won-Hui (Division of Marine Engineering System Mokpo National Maritime University)
  • 최재혁 (한국해양대학교 기관시스템공학부) ;
  • 한원희 (목포해양대학교 기관시스템공학부)
  • Received : 2012.01.26
  • Accepted : 2012.02.23
  • Published : 2012.02.28

Abstract

In order to investigate the effect of n-heptane mixing on PAH and soot formation, small amount of n-heptane has been mixed in counterflow 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 n-heptane in ethylene diffusion flame produces more PAHs and soot than those of pure ethylene flame. However, signals of LIF for 20% n-heptane mixture flame were lower than that of pure ethylene flame. It can be considered that the enhancement of PAH and soot formation by the n-heptane mixing of ethylene can be explained by methyl($CH_3$) radical in the low temperature region. And it can be found that reaction rate of H radical for 10% n-heptane plays a crucial role for benzene formation.

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.

Keywords

References

  1. 윤두호, 윤석훈, 최재혁(2010), 대체 연료인 DME 혼합에 의한 대향류 에틸렌 확산화염내 매연 생성에 대한 실험적 연구, 해양환경안전학회지, 제16권, 제3호, pp. 241-322.
  2. Andrae, J. C. G. and R. A. Head(2009), HCCI experiments with gasoline surrogate fuels modeled by a semidetailed chemical kinetic model Original, Combustion and Flame 156, pp. 842-851. https://doi.org/10.1016/j.combustflame.2008.10.002
  3. Andrae, J., D. Johansson, P. Bjornbom, P. Risberg and G. Kalghatgi(2005), CO-oxidation in the Auto-ignition of Primary Reference Fuels and N-heptane/Toluene Blends, Combustion and Flame, Vol. 140, No. 4, pp. 267-286. https://doi.org/10.1016/j.combustflame.2004.11.009
  4. Choi, J. H., O. Fujita, T. Tsuiki, J. Kim and S. H. Chung(2008), Experimental study on thermophoretic deposition of soot particles in laminar diffusion flames along a solid wall in Microgravity, Experimental Thermal and Fluid, Sci., Vol. 32, pp. 1484-1491. https://doi.org/10.1016/j.expthermflusci.2008.03.008
  5. EEB; The European Environment Bureau(2004), Air Pollution from ships, pp. 1-15.
  6. Gauthier, B. M., D. F. Davidson and R. K. Hanson (2004), Shock tube determination of ignition delay times in full-blend and surrogate fuel mixtures, Combustion and Flame, Vol. 139, pp. 300-311. https://doi.org/10.1016/j.combustflame.2004.08.015
  7. Hernandez, J. J., J. Sanz-Argent, J. Benajes and S. Molina(2008), Selection of a Diesel Fuel Surrogate for the Prediction of Auto-ignition under HCCI Engine Conditions, Fuel, Vol. 87, No. 6, pp. 655-665. https://doi.org/10.1016/j.fuel.2007.05.019
  8. Maroteaux, F. and L. Noel(2006), Development of a Reduced N-heptane Oxidation Mechanism for HCCI Combustion Modeling, Combustion and Flame, Vol. 146, No. 1-2, pp. 246-267. https://doi.org/10.1016/j.combustflame.2006.03.006
  9. McEnally, C. S. and L. D. Pfefferle(2007), The effects of dimethyl ether and ethanol on benzene and soot formation in ethylene nonpremixed flames, Proc. Combust. Inst., Vol. 31, pp. 603-610.
  10. Vanhove, G., R. Minetti, S. Touchard, R. Fournet, P. A. Glaude and F. Battin-Leclerc(2006), Experimental and modeling study of the autoignition of 1-hexene /isooctane mixtures at low temperatures, Combustion and Flame, Volume 145, Issues 1-2, pp. 272-281. https://doi.org/10.1016/j.combustflame.2005.10.007
  11. Yoon, S. S.(2005), Role of odd carbon chemistry on soot formation in ethylene-base diffusion flames with fuel mixing, Seoul National University, ph. D. thesis, pp. 56-73.
  12. Yoon, S. S., S. M. Lee and S. H. Chung(2005), Effect of mixing methane, ethane, propane, and propene on the synergistic effect of PAH and soot formation in ethylene-base counterflow diffusion flames, Proc. Combust.Inst., Vol. 30, pp. 1417-1424.

Cited by

  1. Measurement of soot primary particle size in co-flow laminar diffusion flames of n-heptane at elevated pressures vol.238, pp.None, 2012, https://doi.org/10.1016/j.combustflame.2021.111897