OH/CH_2O基于PLIF测量得到的火焰面密度比较研究
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摘要
通过分析平面激光诱导荧光(PLIF)图像,可获得火焰中的火焰面密度(Σ)等参数.但目前少有工作将基于不同组分测量的Σ进行比较.针对这一问题,应用PLIF技术同时测量甲烷/空气预混湍流火焰的OH和CH2O分布,通过分析OH-PLIF和CH2O-PLIF的图像计算Σ,并比较不同火焰条件下两种计算方法的差别,得到如下结果:在y/d较小的火焰区域两种计算方法得到的Σ值基本一致;随着燃烧器出口速度增加或当量比接近1,在更小的y/d下两种计算方法测量得到的Σ值基本吻合.
The flame surface density(Σ) can be obtained by analyzing the plane laser-induced fluorescence(PLIF) image parameters. However,few researchers have addressed different Σ measurements based on different components. To this end,the PLIF technique was used to simultaneously measure the OH and CH_2O distribution in premixed methane/air turbulent flames. Σ was calculated by analyzing the images of OH-PLIF and CH_2O-PLIF,and the differences between the two calculation methods under different flame conditions were compared. The Σ values obtained by the two calculation methods in smaller y/d flame areas were identical. As the burner exit velocity increases or the equivalence ratio approaches the unity,the Σ values measured by the two calculation methods at the smaller y/d are consistent.
The flame surface density(Σ) can be obtained by analyzing the plane laser-induced fluorescence(PLIF) image parameters. However,few researchers have addressed different Σ measurements based on different components. To this end,the PLIF technique was used to simultaneously measure the OH and CH_2O distribution in premixed methane/air turbulent flames. Σ was calculated by analyzing the images of OH-PLIF and CH_2O-PLIF,and the differences between the two calculation methods under different flame conditions were compared. The Σ values obtained by the two calculation methods in smaller y/d flame areas were identical. As the burner exit velocity increases or the equivalence ratio approaches the unity,the Σ values measured by the two calculation methods at the smaller y/d are consistent.
引文
[1]Zhang M,Wang J,Xie Y,et al.Measurement on instantaneous flame front structure of turbulent premixed CH4/H2/air flames[J].Experimental Thermal and Fluid Science,2014,52(1):288-296.
[2]Driscoll J F.Turbulent premixed combustion:Flamelet structure and its effect on turbulent burning velocities[J].Progress in Energy and Combustion Science,2008,34(1):91-134.
[3]张猛,王金华,俞森彬,等.自适应阈值二值法提取湍流火焰前锋面结构[J].燃烧科学与技术,2016,22(3):212-217.Zhang Meng,Wang Jinhua,Yu Senbin,et al.Flame front tracking of turbulent premixed flames using adaptive threshold binarization[J].Journal of Combustion Science and Technology,2016,22(3):212-217(in Chinese).
[4]Kobayashi H,Seyama K,Hagiwara H,et al.Burning velocity correlation of methane/air turbulent premixed flames at high pressure and high temperature[J].Proceedings of the Combustion Institute,2005,30(1):827-834.
[5]Griebel P,Siewert P,Jansohn P.Flame characteristics of turbulent lean premixed methane/air flames at high pressure:Turbulent flame speed and flame brush thickness[J].Proceedings of the Combustion Institute,2007,31(2):3083-3090.
[6]Sj?holm J,Rosell J,Li B,et al.Simultaneous visualization of OH,CH,CH2O and toluene PLIF in a methane jet flame with varying degrees of turbulence[J].Proceedings of the Combustion Institute,2013,34(1):1475-1482.
[7]Brackmann C,Nygren J,Bai X,et al.Laser-induced fluorescence of formaldehyde in combustion using third harmonic Nd:YAG laser excitation[J].Spectrochimica Acta Part A:Molecular and Biomolecular Spectroscopy,2003,59(14):3347-3356.
[8]Gabet K N,Patton R A,Jiang N,et al.High-speed CH2O PLIF imaging in turbulent flames using a pulseburst laser system[J].Applied Physics B:Lasers and Optics,2012,106(3):569-575.
[9]Li B,Zhang D,Li X,et al.Strategy of interferencefree atomic hydrogen detection in flames using femtosecond multi-photon laser-induced fluorescence[J].International Journal of Hydrogen Energy,2017,42(6):3876-3880.
[10]Li Z S,Kiefer J,Zetterberg J,et al.Development of improved PLIF CH detection using an Alexandrite laser for single-shot investigation of turbulent and lean flames[J].Proceedings of the Combustion Institute,2007,31(1):727-735.
[11]Li B,Baudoin E,Yu R,et al.Experimental and numerical study of a conical turbulent partially premixed flame[J].Proceedings of the Combustion Institute,2009,32(2):1811-1818.
[12]Li B,Zhang D,Yao M,et al.Strategy for single-shot CH3 imaging in premixed methane/air flames using photofragmentation laser-induced fluorescence[J].Proceedings of the Combustion Institute,2017,36(3):4487-4495.
[13]Li Z S,Li B,Sun Z W,et al.Turbulence and combustion interaction:High resolution local flame front structure visualization using simultaneous single-shot PLIFimaging of CH,OH,and CH2O in a piloted premixed jet flame[J].Combustion and Flame,2010,157(6):1087-1096.
[14]Zhang M,Wang J,Wu J,et al.Flame front structure of turbulent premixed flames of syngas oxyfuel mixtures[J].International Journal of Hydrogen Energy,2014,39(10):5176-5185.
[15]Shepherd I G,Cheng R K.The burning rate of premixed flames in moderate and intense turbulence[J].Combustion and Flame,2001,127(3):2066-2075.
[16]Filatyev S A,Driscoll J F,Carter C D,et al.Measured properties of turbulent premixed flames for model assessment,including burning velocities,stretch rates,and surface densities[J].Combustion and Flame,2005,141(1/2):1-21.
[17]Donbar J M,Driscoll J F,Carter C D.Reaction zone structure in turbulent nonpremixed jet flames-from CH-OH PLIF images[J].Combustion and Flame,2000,122(1/2):1-19.
[18]Duwig C,Li B,Li Z S,et al.High resolution imaging of flameless and distributed turbulent combustion[J].Combustion and Flame,2012,159(1):306-316.
[2]Driscoll J F.Turbulent premixed combustion:Flamelet structure and its effect on turbulent burning velocities[J].Progress in Energy and Combustion Science,2008,34(1):91-134.
[3]张猛,王金华,俞森彬,等.自适应阈值二值法提取湍流火焰前锋面结构[J].燃烧科学与技术,2016,22(3):212-217.Zhang Meng,Wang Jinhua,Yu Senbin,et al.Flame front tracking of turbulent premixed flames using adaptive threshold binarization[J].Journal of Combustion Science and Technology,2016,22(3):212-217(in Chinese).
[4]Kobayashi H,Seyama K,Hagiwara H,et al.Burning velocity correlation of methane/air turbulent premixed flames at high pressure and high temperature[J].Proceedings of the Combustion Institute,2005,30(1):827-834.
[5]Griebel P,Siewert P,Jansohn P.Flame characteristics of turbulent lean premixed methane/air flames at high pressure:Turbulent flame speed and flame brush thickness[J].Proceedings of the Combustion Institute,2007,31(2):3083-3090.
[6]Sj?holm J,Rosell J,Li B,et al.Simultaneous visualization of OH,CH,CH2O and toluene PLIF in a methane jet flame with varying degrees of turbulence[J].Proceedings of the Combustion Institute,2013,34(1):1475-1482.
[7]Brackmann C,Nygren J,Bai X,et al.Laser-induced fluorescence of formaldehyde in combustion using third harmonic Nd:YAG laser excitation[J].Spectrochimica Acta Part A:Molecular and Biomolecular Spectroscopy,2003,59(14):3347-3356.
[8]Gabet K N,Patton R A,Jiang N,et al.High-speed CH2O PLIF imaging in turbulent flames using a pulseburst laser system[J].Applied Physics B:Lasers and Optics,2012,106(3):569-575.
[9]Li B,Zhang D,Li X,et al.Strategy of interferencefree atomic hydrogen detection in flames using femtosecond multi-photon laser-induced fluorescence[J].International Journal of Hydrogen Energy,2017,42(6):3876-3880.
[10]Li Z S,Kiefer J,Zetterberg J,et al.Development of improved PLIF CH detection using an Alexandrite laser for single-shot investigation of turbulent and lean flames[J].Proceedings of the Combustion Institute,2007,31(1):727-735.
[11]Li B,Baudoin E,Yu R,et al.Experimental and numerical study of a conical turbulent partially premixed flame[J].Proceedings of the Combustion Institute,2009,32(2):1811-1818.
[12]Li B,Zhang D,Yao M,et al.Strategy for single-shot CH3 imaging in premixed methane/air flames using photofragmentation laser-induced fluorescence[J].Proceedings of the Combustion Institute,2017,36(3):4487-4495.
[13]Li Z S,Li B,Sun Z W,et al.Turbulence and combustion interaction:High resolution local flame front structure visualization using simultaneous single-shot PLIFimaging of CH,OH,and CH2O in a piloted premixed jet flame[J].Combustion and Flame,2010,157(6):1087-1096.
[14]Zhang M,Wang J,Wu J,et al.Flame front structure of turbulent premixed flames of syngas oxyfuel mixtures[J].International Journal of Hydrogen Energy,2014,39(10):5176-5185.
[15]Shepherd I G,Cheng R K.The burning rate of premixed flames in moderate and intense turbulence[J].Combustion and Flame,2001,127(3):2066-2075.
[16]Filatyev S A,Driscoll J F,Carter C D,et al.Measured properties of turbulent premixed flames for model assessment,including burning velocities,stretch rates,and surface densities[J].Combustion and Flame,2005,141(1/2):1-21.
[17]Donbar J M,Driscoll J F,Carter C D.Reaction zone structure in turbulent nonpremixed jet flames-from CH-OH PLIF images[J].Combustion and Flame,2000,122(1/2):1-19.
[18]Duwig C,Li B,Li Z S,et al.High resolution imaging of flameless and distributed turbulent combustion[J].Combustion and Flame,2012,159(1):306-316.