基于自发瑞利-布里渊散射测量空气的温度
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摘要
瑞利-布里渊散射的散射截面比拉曼散射大,因而其在大气散射中实现对大气对流层温度廓线的准确测量方面具有一定的优势,同时利用瑞利-布里渊散射实现高压环境下温度的准确测量对于航天飞机主引擎状态的监测和超燃发动机燃烧室参数测量方面具有重要意义。基于自发瑞利-布里渊散射分别采用反卷积方法和卷积方法来实现空气在不同压力条件下的温度反演,研究引起温度反演误差的原因,并对利用两种方法获得的温度测量结果进行了比较。在利用基于维纳滤波器的反卷积方法对测量光谱直接处理实现温度反演之前,首先利用反卷积方法对由自发瑞利-布里渊散射模型与仪器函数卷积得到的卷积光谱进行处理获得反卷积光谱,将反卷积光谱与未经卷积的理论计算光谱进行比较实现温度反演,并基于温度反演误差小于1.0 K,光谱拟合误差相对较小,光谱处理时间短的参数优化原则对反卷积方法中的关键参数奇异值叠加数进行了优化处理,得到优化后的奇异值叠加数为150。随后实验测量了由532 nm波长的连续激光激发的纯净空气在温度为294.0 K,压强为1～7 bar条件下的自发瑞利-布里渊散射光谱,并结合理论计算光谱和最小χ~2值原理对光谱信号散射角进行优化,优化值为90.7°,同时利用反卷积和卷积方法分别对实验测量光谱进行处理实现空气在不同压强下的温度反演。实验结果表明反卷积方法在一定程度上可以提高信号光谱分辨率,而且利用反卷积和卷积方法均可以实现空气在不同压力(1～7 bar)条件下温度的准确测量,温度测量的最大误差均小于2.0 K;利用反卷积方法的温度反演结果随着气体压强的增大随之得到改善,实现温度反演测量所需要的光谱处理时间减少;在空气压强较低(≤2 bar)时,由卷积方法获得的温度反演结果要优于反卷积方法,压强较高(>2 bar)时,两种方法的温度反演结果相近,其绝对误差均小于1.0 K。通过分析得到引起两种方法温度反演误差的原因主要包括环境温度的波动(±0.2 K),散射角存在一定的不确定度以及气体的各已知参数的微量偏差对温度测量结果的影响以及反卷积对光谱噪声的非线性放大引起的光谱扰动对温度测量结果的影响。在实验中可以通过提高测量光谱的信噪比、提高散射角的优化精度及改善反卷积方法来获得更加准确的参数测量结果。
The scattering cross section of Rayleigh-Brillouin is bigger than that of Raman scattering and it hence has an advantage in accurate tropospheric temperature profiling measurement. Moreover, accurate measurement of temperature under high pressure environment using Rayleigh Brillouin scattering is of great significance to monitoring of Space Shuttle Main Engine(SSME) Preburner and the scramjet engine. Both the deconvolution method and the convolution method are used to achieve the temperature retrieving of air under different pressures based on the spontaneous Rayleigh-Brillouin scattering. And the reasons induced the temperature retrival error are studied and a comparison of temperature measurement between the two methods is made. Before the deconvolution method based on Wiener filterbeing performed on the measured spectrum directly, the convolved spectra between the spontaneous Rayleigh-Brillouin scattering model and instrument transmission function are deconvolved to obtain the deconvolved spectra and the decovolved spectra are compared with the theoretical calculation spectra to retrieve temperatures. And the optimized singular value stacking number being 150, which is the key parameter of the deconvolution method, is obtained on account of temperature retriecal error being less than 1.0 K, the relatively unobvious fitting error and the short time consumption of retrieving temperature. And the spontaneous Rayleigh-Brillouin scattering spectra of air induced by the wavelength of 532 nm of laser under the pressure of 1～7 bar at the temperature of 294.0 K are measured in experiment and the optimized scattering angle of 90.7° is obtained by the combination of theoretical spectrum and the principle of minimum value of χ~2. After that, the deconvolution method and the convolution method are used to retrieve temperatures severally. Experiment results demonstrate that the spectral resolution is improved by using deconvolution method to some extent. Meanwhile, both the deconvolution method and the convolution method have good performance on temperature measurement under different pressures and the maximum errors between the retrieved temperature and the reference temperature are less than 2.0 K, temperature retrieving results of the deconvolution method are improved and time consumption of retrieving temperature is reduced with the pressure increasing, and temperature retrieving results using convolution method are better than those using the deconvolution method when the air pressure is low(≤2 bar), however, the results of both methods are close to each other and the absolute temperature errorsareless than 1. 0 K when the air pressure is high(>2 bar). By analysis, it is found that the factors causing the temperature retrieval errors for both methods include the temperature fluctuations(±0.2 K), the effect of uncertainty of scattering angle and the known parameters on temperature retrieving and the spectral disturbancescaused by the nonlinear amplification of spectral noise of deconvolution method. The parameter measurement result can be improved in experiment by improving the signal-to-noise ratio of measured spectrum, the accuracy of optimized scattering angle and the deconvolution method.
The scattering cross section of Rayleigh-Brillouin is bigger than that of Raman scattering and it hence has an advantage in accurate tropospheric temperature profiling measurement. Moreover, accurate measurement of temperature under high pressure environment using Rayleigh Brillouin scattering is of great significance to monitoring of Space Shuttle Main Engine(SSME) Preburner and the scramjet engine. Both the deconvolution method and the convolution method are used to achieve the temperature retrieving of air under different pressures based on the spontaneous Rayleigh-Brillouin scattering. And the reasons induced the temperature retrival error are studied and a comparison of temperature measurement between the two methods is made. Before the deconvolution method based on Wiener filterbeing performed on the measured spectrum directly, the convolved spectra between the spontaneous Rayleigh-Brillouin scattering model and instrument transmission function are deconvolved to obtain the deconvolved spectra and the decovolved spectra are compared with the theoretical calculation spectra to retrieve temperatures. And the optimized singular value stacking number being 150, which is the key parameter of the deconvolution method, is obtained on account of temperature retriecal error being less than 1.0 K, the relatively unobvious fitting error and the short time consumption of retrieving temperature. And the spontaneous Rayleigh-Brillouin scattering spectra of air induced by the wavelength of 532 nm of laser under the pressure of 1～7 bar at the temperature of 294.0 K are measured in experiment and the optimized scattering angle of 90.7° is obtained by the combination of theoretical spectrum and the principle of minimum value of χ~2. After that, the deconvolution method and the convolution method are used to retrieve temperatures severally. Experiment results demonstrate that the spectral resolution is improved by using deconvolution method to some extent. Meanwhile, both the deconvolution method and the convolution method have good performance on temperature measurement under different pressures and the maximum errors between the retrieved temperature and the reference temperature are less than 2.0 K, temperature retrieving results of the deconvolution method are improved and time consumption of retrieving temperature is reduced with the pressure increasing, and temperature retrieving results using convolution method are better than those using the deconvolution method when the air pressure is low(≤2 bar), however, the results of both methods are close to each other and the absolute temperature errorsareless than 1. 0 K when the air pressure is high(>2 bar). By analysis, it is found that the factors causing the temperature retrieval errors for both methods include the temperature fluctuations(±0.2 K), the effect of uncertainty of scattering angle and the known parameters on temperature retrieving and the spectral disturbancescaused by the nonlinear amplification of spectral noise of deconvolution method. The parameter measurement result can be improved in experiment by improving the signal-to-noise ratio of measured spectrum, the accuracy of optimized scattering angle and the deconvolution method.
引文
[1] Alpers M,Eixmann R,Frickebegemann C,et al.Atmospheric Chemistry & Physics Discussions,2004,4(1):793.
[2] Macintyre R,Tan T,Heywood A,et al.Atmospheric Chemistry & Physics,2008,8(2):7569.
[3] Behrendt A,Reichardt J.Applied Optics,2000,39(9):1372.
[4] Witschas B.Research Topics in Aerospace,2012:69.
[5] Seasholtz R G.Structural Integrity and Durability of Reusable Space Propulsion Systems,1991:21.
[6] Witschas B,Lemmerz C,Reitebuch O.Optics Letters,2014,39(7):1972.
[7] Witschas B,Gu Z,Ubachs W.Optics Express,2014,22(24):29655.
[8] Gu Z,Witschas B,van de Water W,et al.Applied Optics,2013,52(19):4640.
[9] SHANG Jing-cheng,WU Tao,HE Xing-dao,et al(商景诚,吴涛,何兴道,等).Acta Physica Sinica(物理学报),2018,67(3):037801.
[10] Gerakis A,Shneider M N,Stratton B C.Applied Physics Letters,2016,109(3):031112.
[11] WU Tao,SHANG Jing-cheng,HE Xing-dao,et al(吴涛,商景诚,何兴道,等).Acta Physica Sinica(物理学报),2018,67(7):077801.
[12] Gu Z,Ubachs W.Journal of Chemical Physics,2014,141(10):375.
[13] Vieitez M O,van Duijn E J,Ubachs W,et al.Physical Review A,2010,82:043836.
[14] Gu Z,Ubachs W.Optics Letters,2013,38(7):1110.
[15] Shneider M N,Pan X.Physical Review A,2005,71(4):45801.
[16] Meijer A S,de Wijn A S,Peters M F,et al.Journal of Chemical Physics,2010,133(16):164315.
[17] Wu T,Shang J C,Yang C Y,et al.AIP Advances,2018,8(1):015210.
[18] Boyd R W.Nonlinear Optics.2nd ed.New York:Academic Press,2003.
[19] Fabelinskii I L.Molecular Scattering of Light.New York:Springer,1968.
[20] Boley C D,Desai R C,Tenti G.Canadian Journal of Physics,1972,50(18):2158.
[21] Tenti G,Boley C D,Desai R C.Canadian Journal of Physics,1974,52(4):285.
[22] White F M.Viscous Fluid Flow.3rd ed.New York:McGraw-Hill,2006.287.
[23] Witschas B,Lemmerz C,Reitebuch O.Applied Optics,2012,51(25):6207.
[24] Golub G H,Reinsch C.Numerische Mathematik,1970,14(5):403.
[25] Henry E R,Hofrichter J.Methods in Enzymology,1992,210(1):129.
[26] Hansen P C.Society for Industrial and Applied Mathematics,1990,11(3):503.
[2] Macintyre R,Tan T,Heywood A,et al.Atmospheric Chemistry & Physics,2008,8(2):7569.
[3] Behrendt A,Reichardt J.Applied Optics,2000,39(9):1372.
[4] Witschas B.Research Topics in Aerospace,2012:69.
[5] Seasholtz R G.Structural Integrity and Durability of Reusable Space Propulsion Systems,1991:21.
[6] Witschas B,Lemmerz C,Reitebuch O.Optics Letters,2014,39(7):1972.
[7] Witschas B,Gu Z,Ubachs W.Optics Express,2014,22(24):29655.
[8] Gu Z,Witschas B,van de Water W,et al.Applied Optics,2013,52(19):4640.
[9] SHANG Jing-cheng,WU Tao,HE Xing-dao,et al(商景诚,吴涛,何兴道,等).Acta Physica Sinica(物理学报),2018,67(3):037801.
[10] Gerakis A,Shneider M N,Stratton B C.Applied Physics Letters,2016,109(3):031112.
[11] WU Tao,SHANG Jing-cheng,HE Xing-dao,et al(吴涛,商景诚,何兴道,等).Acta Physica Sinica(物理学报),2018,67(7):077801.
[12] Gu Z,Ubachs W.Journal of Chemical Physics,2014,141(10):375.
[13] Vieitez M O,van Duijn E J,Ubachs W,et al.Physical Review A,2010,82:043836.
[14] Gu Z,Ubachs W.Optics Letters,2013,38(7):1110.
[15] Shneider M N,Pan X.Physical Review A,2005,71(4):45801.
[16] Meijer A S,de Wijn A S,Peters M F,et al.Journal of Chemical Physics,2010,133(16):164315.
[17] Wu T,Shang J C,Yang C Y,et al.AIP Advances,2018,8(1):015210.
[18] Boyd R W.Nonlinear Optics.2nd ed.New York:Academic Press,2003.
[19] Fabelinskii I L.Molecular Scattering of Light.New York:Springer,1968.
[20] Boley C D,Desai R C,Tenti G.Canadian Journal of Physics,1972,50(18):2158.
[21] Tenti G,Boley C D,Desai R C.Canadian Journal of Physics,1974,52(4):285.
[22] White F M.Viscous Fluid Flow.3rd ed.New York:McGraw-Hill,2006.287.
[23] Witschas B,Lemmerz C,Reitebuch O.Applied Optics,2012,51(25):6207.
[24] Golub G H,Reinsch C.Numerische Mathematik,1970,14(5):403.
[25] Henry E R,Hofrichter J.Methods in Enzymology,1992,210(1):129.
[26] Hansen P C.Society for Industrial and Applied Mathematics,1990,11(3):503.
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