0~#柴油燃烧初期火焰光谱分析

为推进柴油燃烧初期智能识别与抑制灭火技术的发展,通过小尺度油池实验和光谱分析的方法,首次对0~#柴油燃烧初期火焰光谱进行了初步研究,得到0~#柴油燃烧初期火焰光谱的整体特性:在200~380nm的近紫外波段,光谱强度最弱,强度与波长关系不大,特征谱带数量最少,基本没有明显的谱峰;在380~780nm的可见光波段,光谱强度最强,强度随波长的增大而增大,特征谱带最多,存在较多明显的谱峰;在780~1 100nm的近红外波段,光谱强度相对较大,在780nm处出现强度的拐点,强度随波长的增大而减小,特征谱带较多,存在一定数量较为明显的谱峰。进一步对其火焰光谱进行分析得到:燃烧过程中主要的中间产物自由基包括OH,CN,CH,C_2,H2O等;火焰光谱中主要的特征谱带包括OH自由基306.4nm系统谱带和振动转动谱带、CN自由基紫色光区和红色光区谱带、CH自由基431.5nm谱带、C_2自由基Swan和Phillips近红外谱带、H2O分子振动转动谱带等;特征谱带特征波长及时间的分布情况和主要生成机制;在本实验批次0~#柴油中存在金属K元素,其特征谱线在761和769nm处出现明显的谱峰;在431,512,516,547,589,766,769,891和927nm出现较为明显的特征谱峰,适合作为0~#柴油燃烧初期火焰识别的标志。

Analysis of Flame Spectrum at the Initial Stage of 0# Diesel Oil Combustion

With small-scale oil pool experimental and spec tral analysis method,the flame spectrum in initial stage of 0# diesel oil com bustion was conducted a preliminary study for the first time,which was used to develop the technique of intelligent identification and suppression of fire exti nguishing at the initial stage of diesel oil combustion.It educed the overall c haracteristics flame spectrum at the initial stage of 0# diesel oil combustion: in 200~380 nm waveleng th of near-ultraviolet bands,the spectral intensity is the weakest,the spec tral intensity does not change with wavelength,the number of characteristics s pectral bands is minimum,the number of obvious characteristics spectral peaks is almost none;in 380~780 nm wavelength of visible bands,the spectral inten sity is the strongest,the spectral intensity increases with wavelength,the n umber of characteristics spectral bands is maximum,the number of obvious char acteristics spectral peaks is large;in 780~1 100 nm wavelength of near-infra red bands,the spectral intensity is relatively strong,the inflection point o f spectral intensity appears in 780 nm,the appeared intensity decreases with w avelength,the number of characteristics spectral bands is relatively large,t he number of obvious characteristics spectral peaks is at a certain number.It is educed through further analysis of the flame spectrum that: the primary inte rmediate radicals includes OH,CN,CH,C2,H2O,etc;the primary chara cteristic spectral bands includes the OH racial bands of 3 064 System and Vib ration-Rotation bands,the CN racial bands of Violet System and Red System,t he CH racial bands of 4 315 System,the C2 racial bands of The Swan system and Phillips Near Infra-red System,the H2O molecular Vibration-Rotation b ands,etc;the bands and time distribution of primary intermediate radicals an d its main generation mechanism;the existence of potassium in this experimen tal batches of 0# diesel oil and the spectral peak of spectral lines in 766 a nd 769 nm is obvious;the peak of spectral intensity in 431,512,516,547,589,766,769,891,927 nm is obvious,and it suitable for the sign of fla me identification at the initial stage of 0# diesel oil combustion.