利用激光诱导炽光研究高压环境下液体燃料层流扩散火焰碳烟分布的二维图像

doi:10.7517/j.issn.1674-0475.2017.02.106

摘要/Abstract

摘要：

研究了在高压环境下压力对液体燃料的碳烟的层流扩散火焰碳烟生成的影响。利用激光诱导炽光和消光法相结合的方法，获得了层流扩散火焰的碳烟分布二维图像，测量和分析了正庚烷的层流扩散火焰的碳烟体积分数生成随压力变化的规律。然后，引入特别设计的“滴入式火焰”装置，该设计为两种以上液体混合燃料的层流扩散火焰碳烟生成的测量提供了保障。最后，定量地分析和对比了饱和环状分子结构（环己烷和环己醇）和直链分子结构（正己烷和1-己醇）的液体燃油的层流扩散火焰的碳烟生成趋势，结果表明，环状分子结构燃油的碳烟生成倾向要强于它们对应的线性分子结构的燃油。

关键词: 层流扩散火焰, 液体燃料, 碳烟分布, 分子结构, 高压, 激光诊断

Abstract:

This research focuses on the effects of an increasing pressure on the soot formation during combustion of vaporized liquid fuel. Firstly, soot formation is measured in a laminar diffusion flame of n-heptane up to 3.0 bar. The soot volume fraction in the diffusion flames has been measured using Laser Induced Incandescence (LII) calibrated by means of the Line of Sight Attenuation (LOSA) technique. The 2-D images of soot distributions have been captured, and the integral soot volume fractions show power law dependence on pressures. Secondly, a specially designed High fueling system (called "doped flame") is presented in this paper. This setup allows for soot measurements in laminar diffusion flames of liquid fuel blends at elevated pressure. Fuels with two typical molecular structures, namely linear and saturated cyclic hydrocarbons, are examined in both non-oxygenated (n-hexane and cyclohexane) and oxygenated form (1-hexanol and cyclohexanol). The experiment data suggests that soot is more prevalent for cyclic structures relative to their linear counterparts.

Key words: laminar diffusion flame, liquidfuels, soot distributions, molecular structure, elevated pressure, laser diagnostics

周磊, 张红兴, 王震. 利用激光诱导炽光研究高压环境下液体燃料层流扩散火焰碳烟分布的二维图像[J]. 影像科学与光化学, 2017, 35(2): 106-113.

ZHOU Lei, ZHANG Hongxing, WANG Zhen. Study on Two-dimensional Images of Soot Distributions in Laminar Diffusion Flames of Liquid Fuelsat Elevated Pressure by Laser Induced Incandescence (LII)[J]. Imaging Science and Photochemistry, 2017, 35(2): 106-113.

参考文献

[1] Xue J, Grift T E, Hansena A C. Effect of biodiesel on engine performances and emissions[J]. Renewable & Sustainable Energy Reviews, 2011, 15(2):1098-1116.
[2] Giuliano P, Stefania C, Alessandra S. Effects of particulate matter (PM10, PM2.5 and PM1) on the cardiovascular system[J]. Toxicology, 2009, 261(1-2):1-8.
[3] Lapuerta M, Armas O,Rodríguez-Fernández J. Effect of biodiesel fuels on diesel engine emissions[J]. Progress in Energy & Combustion Science, 2008, 34(2):198-223.
[4] Zhou L. Emission reduction in compression-ignition engines by fuel tuning[D]. Eindhoven:Eindhoven University of Technology, 2013.
[5] Zhou L, Heuser B, Boot M D, Kremer F, Pischinger S. Performance and emissions of lignin and cellulose based oxygenated fuels in a compression-ignition engine[R]. SAE Technical Paper, 2015-01-0910.
[6] Heuser B, Kremer F, Pischinger S, Julis J. Optimization of diesel combustion and emissions with newly derived biogenic alcohols[R]. SAE Technical Paper, 2013-01-2690.
[7] Glassman I. Soot formation in combustion processes[J]. Proceedings of the Combustion Institute, 1989, 22(1):295-311.
[8] Wang H. Formation of nascent soot and other condensed-phase materials in flames[J]. Proceedings of the Combustion Institute, 2011, 33(1):41-67.
[9] Cain J P, Gassman P L, Wang H, Laskin A. Micro-FTIR study of soot chemical composition-evidence of aliphatic hydrocarbons on nascent soot surfaces[J]. Physical Chemistry Chemical Physics, 2010, 12(20):5206-18.
[10] Donkerbroek A J, Boot M D, Luijten C C M. Flame lift-off length and soot production of oxygenated fuels in relation with ignition delay in a DI heavy-duty diesel engine[J]. Combustion and Flame, 2011, 158(3):525-538.
[11] Kitamura T. Detailed chemical kinetic modeling of diesel spray combustion with oxygenated fuels[R]. SAE paper, 2001-01-1262.
[12] Tree D R, Svensson K I. Soot processes in compression ignition engines[J]. Progress in Energy & Combustion Science, 2007, 33(3):272-309.
[13] Zhou L, Dam N J, Boot M D, Goey L P H de. Investigation of the effect of molecular structure on sooting tendency in laminar diffusion flames at elevated pressure[J]. Combustion and Flame, 2014, 161(10):2669-2677.
[14] Schulz C, Kock B F, Hofmann M, Michelsen H A, Will S, Bougie B, Suntz R, Smallwood G J. Laser-induced incandescence:recent trends and current questions[J]. Applied Physics B, 2006, 83(3):333-354.
[15] Michelsen H A. Understanding and predicting the temporal response of laser-induced incandescence from carbonaceous particles[J]. Journal of Chemical Physics, 2003, 118(15):7012-7045.
[16] Bassi J, Naftaly M, Miles B, Zhang Y. The investigation of sooty flames using terahertz waves[J]. Flow Measurement & Instrumentation, 2005, 16(5):341-345.
[17] Migliorini F, De Iuliis S, Cignoli F, Zizak G. Absorption correction of two-color laser-induced incandescence signals for soot volume fraction measurements[J]. Applied Optics, 2006, 45(29):7706-7711.
[18] Shaddix C R, Smyth K C. Laser-induced incandescence measurements of soot production in steady and flickering methane, propane, and ethylene diffusion flames[J]. Combustion and Flame, 1996, 107(4):418-452.
[19] Liu F, Thomson K A, Smallwood G J. Effects of soot absorption and scattering on LII intensities in laminar coflow diffusion flames[J]. Journal of Quantitative Spectroscopy & Radiative Transfer, 2008, 109(2):337-348.
[20] Lemaire R, Faccinetto A, Therssen E, Ziskind M, Focsa C, Desgroux P. Experimental comparison of soot formation in turbulent flames of Diesel and surrogate Diesel fuels[J]. Proceedings of the Combustion Institute, 2009, 32(1):737-744.
[21] McCrain L L, Roberts W L. Measurements of the soot volume field in laminar diffusion flames at elevated pressures[J]. Combustion and Flame, 2005, 140(1-2):60-69.
[22] Smooke M D, Long M B, Connelly B C, Colket M B, Hall R J. Soot formation in laminar diffusion flames[J]. Combustion and Flame, 2005, 143(4):613-628.
[23] Menon A V. Effect of m-xylene on soot formation in high pressure diffusion flames[D]. State College:Pennsylvania State University, 2010.
[24] Mouis A G, Menon A,Katta V, Litzinger T A, Linevsky M, Santoro R J, Zeppieri S P, Colket M B, Roquemore W M. Effects of m-xylene on aromatics and soot in laminar, N₂-diluted ethylene co-flow diffusion flames from 1 to 5 atm[J]. Combustion and Flame, 2012, 159(10):3168-3178.
[25] Choi M Y, Jensen K A. Calibration and correction of laser-induced incandescence for soot volume fraction measurements[J]. Combustion and Flame, 1998, 112(4):485-491.
[26] Thomson K A. Soot formation in annular non-premixed laminar flames of methane-air at pressures of 0.1 to 4.0 MPa[D]. Waterloo:University of Waterloo, 2004.
[27] Thomson K A, Gülder Ö L, Weckman E J, Fraser R A, G J, Snelling D R. Soot concentration and temperature measurements in co-annular, non-premixed CH₄/air laminar flames at pressures up to 4 MPa[J]. Combustion and Flame, 2005, 140(3):222-232.
[28] Moss J B, Stewart C D, and Syed K J. Flowfield modelling of soot formation at elevated pressure[J]. Cranfield Institute of Technology, 1989, 22(1):413-423.
[29] Krishnan S S, Lin K C, Faeth G M. Extinction and scattering properties of soot emitted from buoyant turbulent diffusion flames[J]. Journal of Heat Transfer (ASME), 2001, 123(2):331-339.
[30] Krishnan S S, Lin K C, Faeth G M. Optical properties is the visible of overfire soot in large buoyant turbulent diffusion flames[J]. Journal of Heat Transfer (ASME), 2000, 122(3):517-524.
[31] Hofmann M, Bessler W G, Schulz C, Jander H. Laser-induced incandescence for soot diagnostics at high pressures[J]. Applied Optics, 2003, 42(12):2052-2062.
[32] Kadota T, Hiroyasu H, Farazandehmehr A. Soot formation by combustion of a fuel droplet in high pressure gaseous environments[J]. Combustion and Flame, 1977, 29(1):67-75.
[33] Heidermann Th, Jander H, Wagner H Gg. Soot particles in premixed C₂H₄-air-flames at high pressures (p=30-70 bar)[J]. Physical Chemistry Chemical Physics, 1999, 1(1):3497-3502.
[34] Darabkhani H G, Bassi J, Huang H W, Zhang Y. Fuel effects on diffusion flames at elevated pressures[J]. Fuel, 2009, 88(2):264-271.
[35] Darabkhani H G. Experimental investigations on sooty flames at elevated pressures[D]. Manchester:University of Manchester, 2010.
[36] Bento D S, Thomson K A, Gülder Ö L. Soot formation and temperature field structure in laminar propane-air diffusion flames at elevated pressures[J]. Combustion and Flame, 2006, 145(4):765-778.
[37] Joo H I, Gülder Ö L. Soot formation and temperature field structure in co-flow laminar methane-air diffusion flames at pressures from 10 to 60 atm[J]. Proceedings of the Combustion Institute, 2009, 32(1):769-775.
[38] Mandatori P M, Gülder Ö L. Soot formation in laminar ethane diffusion flames at pressures from 0.2 to 3.3 MPa[J]. Proceedings of the Combustion Institute, 2011, 33(1):577-584.
[39] Charest M R J, Groth C P T, Gülder Ö L. Effects of gravity and pressure on laminar coflow methane-air diffusion flames at pressures from 1 to 60 atmospheres[J]. Combustion and Flame, 2011, 158(5):860-875.
[40] Gülder Ö L, Intasopa G, Joo H I, Mandatori P M, Bento D S, Vaillancourt M E. Unified behaviour of maximum soot yields of methane, ethane and propane laminar diffusion flames at high pressures[J]. Combustion and Flame,2011, 158(10):2037-2044.
[41] Kailasanathan R K A, Yelverton T LB, Fang T, Roberts W L. Effect of diluents on soot precursor formation and temperature in ethylene laminar diffusion flames[J]. Combustion and Flame, 2013, 160(3):656-670.
[42] Liu F, Karatas A E, Gülder Ö L, Gu M. Numerical and experimental study of the influence of CO₂ and N₂ dilution on soot formation in laminar coflow C₂H₄/air diffusion flames at pressures between 5 and 20 atm[J]. Combustion and Flame, 2015, 162(5):2231-2247.
[43] Karatas A E, Intasopa G, Gülder Ö L. Sooting behaviour of n-heptane laminar diffusion flames at high pressures[J]. Combustion and Flame, 2013, 160(160):1650-1656.
[44] Khosousi A, Liu F, Seth B D, Eaves N A. Experimental and numerical study of soot formation in laminar coflow diffusion flames of gasoline/ethanol blends[J]. Combustion and Flame, 2015, 162(10):3925-3933.
[45] Consalvi J-L, Liu F. Numerical study of the effects of pressure on soot formation in laminar coflow n-heptane/air diffusion flames between 1 and 10 atm[J]. Proceedings of the Combustion Institute, 2015, 35(2):1727-1734.
[46] Zhou L, Dam N J, Boot M D, Goey L P H de. Measurements of sooting tendency in laminar diffusion flames of n-heptane at elevated pressure[J]. Combustion and Flame, 2013, 160(160):2507-2516.