基于波长调制吸收光谱的燃烧流场二维重建  

Two-Dimensional Reconstruction of Combustion Flow Field Using Wavelength-Modulated Absorption Spectra

作　　者：王兴平 彭冬 李佳胜 金熠[3] 翟超[3] Wang Xingping;Peng Dong;Li Jiasheng;Jin Yi;Zhai Chao(School of Engineering Science,University of Science and Technology of China,Hefei,Anhui 230027,China;Anhui Institute of Optics and Fine Mechanics,Chinese Academy of Science,Hefei,Anhui 230027,China;Experimental Centey,of Engineering and Material Science,University of Science and Technology of China,Hefei,Anhui 230027,China)

机构地区：[1]中国科学技术大学工程科学学院,安徽合肥230027 [2]中国科学院安徽光学精密机械研究所,安徽合肥230027 [3]中国科学技术大学工程与材料科学实验中心,安徽合肥230027

出　　处：《中国激光》2021年第7期196-206,共11页Chinese Journal of Lasers

基　　金：国家自然科学基金(11202204);基础性军工科研院所稳定支持项目(DD2090009001)。

摘　　要：可调谐二极管激光吸收光谱(TDLAS)技术是进行燃烧流场关键参数测量的有效有段。采用近红外水蒸汽的两条吸收线(7168.44 cm^(-1)与7185.60 cm^(-1)),分别利用直接吸收法与波长调制法对不同噪声干扰下的高斯峰流场进行了温度重建的数值仿真。将波长调制法和直接吸收法的二维重建结果进行对比,结果显示基于波长调制法的二维重建有更强的抗噪声能力。以McKenna平面燃烧炉产生的甲烷-空气预混火焰为测量对象,进行了二维温度重建。实验结果显示基于直接吸收法和波长调制法的二维重建的最大偏差分别为8.5%和5.9%,均方相对误差分别为0.0469和0.0268。弱吸收下基于波长调制法的二维重建技术显示了更好的重建效果。Objective The measurement of key parameters of combustion flow field can effectively evaluate combustion efficiency,control pollution emission,and improve energy efficiency.Because of its obvious superior features such as high precision,noncontact measurement,and low cost,tunable diode laser absorption spectroscopy(TDLAS)is an effective way to measure temperature,concentration,velocity,and pressure in combustion flow field.Combined with computerized tomography(CT),TDLAS can achieve two-dimensional(2D)or three-dimensional(3D)tomography.In the 1980s,Emmerman et al.used the direct absorption spectroscopy(DAS)for combustion diagnosis in reactive flows,which verified the feasibility of the method to realize 2D combustion diagnosis.With the development of the laser and reconstruction algorithms,the DAS-based 2D reconstruction technology has begun to be applied to engineering practice.This technology has been successfully used in the Hypersonic International Flight Research Experiment(HIFiRE)conducted by the US Air Force Laboratory and NASA.Although the DAS exhibits many advantages,it is difficult to apply this method under low signal-to-noise ratio(SNR)conditions.The wavelength modulation spectroscopy developed on the basis of the DAS can significantly improve the SNR under weak absorption conditions,thus improving the detection accuracy and detection limit of the absorption spectroscopy.In line-of-sight measurement,the wavelength modulation spectroscopy(WMS)shows good noise resistance and is therefore suitable for the flow field measurement under weak absorption or high-pressure conditions.Calibration-free WMS(CF-WMS)proposed by Hanson's group from Stanford University is one of the widely used WMS methods.As far as we know,the literature mainly focused on numerical simulation analysis for the difference in 2D reconstruction between the DAS and WMS.It is necessary to verify the difference between the two methods by experiment.Methods Combined with the algebraic reconstruction technique(ART),we introduced the principle

关 键 词：激光技术 光谱学 波长调制 二维重建 燃烧诊断 

分 类 号：O433[机械工程—光学工程]