引用本文
白冰, 陈国柱, 杨文斌, 车庆丰, 王林森, 孙伟民, 陈爽. CRDS-CARS- PLIF技术精确定量测量火焰OH浓度实验研究[J]. 光谱学与光谱分析, 2023,43(12): 3955-3962.
BAI Bing, CHEN Guo-zhu, YANG Wen-bin, CHE Qing-feng, WANG Lin-sen, SUN Wei-min, CHEN Shuang. The Study on Precise and Quantitative Measurement of Flame OH Concentration by CRDS-CARS-PLIF Techniques[J]. Spectroscopy and Spectral Analysis, 2023,43(12): 3955-3962.
Doi:10.3964/j.issn.1000-0593(2023)12-3955-08  
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CRDS-CARS- PLIF技术精确定量测量火焰OH浓度实验研究
白冰1,2,3, 陈国柱2,3, 杨文斌2,3, 车庆丰2,3, 王林森2,3, 孙伟民1,*, 陈爽1,2,3,*
1.哈尔滨工程大学物理与光电工程学院, 黑龙江 哈尔滨 150001
2.中国空气动力研究与发展中心空气动力学国家重点实验室, 四川 绵阳 621000
3.中国空气动力研究与发展中心设备设计与测试技术研究所, 四川 绵阳 621000
*通讯作者

白冰, 陈国柱: 共同第一作者

收稿日期: 2022-09-27 修回日期: 2023-04-10 接受日期: 2023-04-10
摘要

在预混甲烷/空气燃烧的平面火焰炉上, 采用脉冲式光腔衰荡光谱技术(cavity ring-down spectroscopy, CRDS)实现了对OH分子浓度的定量测量。 根据光腔衰荡吸收光谱理论, 选取OH的A2Σ+-X2Π(0,0)电子跃迁带中的P1(2)吸收谱线构搭建了一套激光波长在308.6 nm的脉冲CRDS实验装置。 脉冲CRDS装置中的衰荡光腔是由一对反射率为99.7%的高反射镜组成且其衰荡腔的腔长为270 cm, 并测量空腔(光腔中无火焰)的衰荡时间为2.33 μs。 通过理论分析影响浓度精确测量的实验参数, 分别采用平面激光诱导荧光(planar laser induced fluorescence, PLIF)、 相干反斯托克斯拉曼散射(coherent anti-stokes Raman scattering, CARS)和脉冲CRDS三种技术精确测量OH的有效吸收长度、 高温火焰的温度和有效的光腔衰荡时间。 当在平面火焰炉上燃烧预混的甲烷(1.1 L·min-1)和空气(15 L·min-1)且在距离炉面高度为6 mm时, 采用PLIF技术测量的有效吸收长度比直接选用燃烧器炉面直径作为吸收长度的精度提高7.1%, 室温下利用CARS技术测量的温度要比热电偶测量的温度精度提高45%, 衰荡光腔内有火焰且选用非OH吸收波长时测得的光腔衰荡时间要比采用空腔时测得的光腔衰荡时间精度提高21.6%。 因此, 通过以上多种测量技术相结合的方式精准测量各实验参量, 最后得到OH分子数密度在距离炉面高度为6 mm时达到最大值(3.59×1013 molecules·cm-3)且OH浓度精度要比于未修正的OH浓度提高了35.6%。 另外, 在不同当量比下( Φ=0.7~1.1), OH粒子数密度都会随着距离炉面高度的增加而减少, 通过曲线拟合发现OH浓度随着距离炉面高度的增加呈e指数衰减。 在同一燃烧高度的富氧燃烧状态下, OH浓度随着当量比的增加而增加; 当甲烷流量保持恒定时, 富氧燃烧状态下的OH浓度要高于低氧燃烧状态下的OH浓度。 在燃烧场中, 采用这种多光谱技术相结合(CRDS-CARS- PLIF)的精准测量方式不仅能够实现对OH浓度精准的定量测量提高了测量精度, 还可为定量测量其他燃烧产物分子的浓度提供技术支撑, 对研究燃烧化学反应起着至关重要的作用。

关键词: 光腔衰荡光谱; 有效吸收长度; 高温测量; 衰荡时间; OH浓度
中图分类号:O433.1 文献标志码:A
The Study on Precise and Quantitative Measurement of Flame OH Concentration by CRDS-CARS-PLIF Techniques
BAI Bing1,2,3, CHEN Guo-zhu2,3, YANG Wen-bin2,3, CHE Qing-feng2,3, WANG Lin-sen2,3, SUN Wei-min1,*, CHEN Shuang1,2,3,*
1. College of Physics and Optoelectronic Engineering, Harbin Engineering University, Harbin 150001, China
2. State Key Laboratory of Aerodynamics, China Aerodynamics Research and Development Center, Mianyang 621000, China
3. Facility Design and Instrumentation Institute, China Aerodynamics Research and Development Center, Mianyang 621000, China
*Corresponding authors e-mail: sunweimin@hrbeu.edu.cn; chenshuang56@126.com

Biography: BAI Bing, (1990—), Doctoral candidate, College of Physics and Optoelectronic Engineering, Harbin Engineering University e-mail: baibing2022@126.com;CHEN Guo-zhu, (1990—), Engineer, State Key Laboratory of Aerodynamics, China Aerodynamics Research and Development Center e-mail: guozhu108@sina.com BAI Bing and CHEN Guo-zhu: joint first authors

Fund:Foundation item: National Key Research and Development Program of China(2020YFA0405700)
Abstract

In this paper, a pulsed cavity-ring down spectroscopy (CRDS) is employed to measure the quantitative concentration of the OH radical in a plane flame burner with premixed methane/air. By analyzing the cavity ring-down absorption spectrum theory, we select the P1(2) absorption line spectrum of the electronic transition band OH A2Σ+-X2Π(0,0) and build a set of the pulsed CRDS experimental device with a laser wavelength of 308.6 nm. The device of the pulsed CRDS is composed of a pair of mirrors with a reflectance of 99.7%, the cavity length of the ring-down cavity is 270 cm, and the ring-down time of the empty cavity (without a flame in the optical cavity) is 2.33 μs. By analyzing the experimental parameters that affect the precise measurement of concentration, we use Planar Laser Induced Fluorescence (PLIF), Coherent Anti-Stokes Raman Scattering (CARS), and the pulsed CRDS to measure the effective absorption length of OH, high temperature of the flame, and cavity ring-down time. When the premixed methane (1.1 L·min-1) and air (15 L·min-1) are burned in a flat flame burner, and at the height of 6 mm from the burner surface, the precisely measured effective absorption length by PLIF is 7.1% higher than that of directly choosing the diameter of the burner surface as the absorption length, the measured precision of the temperature by CARS is increased by 45% than that measured by the thermocouple under room temperature, the measured precision of the optical cavity ring-down time with flame in the cavity and non-OH absorption wavelength is improved by 21.6% than that measured time of cavity ring-down without a flame in the cavity. By combining the above measurement techniques to measure all experimental parameters precisely, we obtain that the number density of OH molecules (3.59×1013 molecules·cm-3) can reach the maximum value when the height from the furnace burner is 6 mm, and the precision of OH concentration is 35.6% higher than that of the unmodified OH concentration. Under different equivalence ratios ( Φ=0.7~1.1), with the increase of the height from the burner surface, the number of OH particles gradually decreases, and the curve fitting shows that the OH concentration decreases in an e-exponential decay. At the same combustion height, the concentration of OH increases with the increase of equivalent ratios. When the methane flow rate is kept constant, the OH concentration in the oxygen-rich combustion condition is higher than in the low-oxygen combustion condition. In the combustion field, the precise measurement method with the multi-spectral technology (CRDS-CARS-PLIF) can achieve the precise quantitative measurement of OH concentration and provide technical support for the quantitative measurement of the concentration of other combustion product molecules, which plays a crucial role in the study of combustion chemical reactions.

Keyword: CRDS (cavity ring-down spectroscopy); Effective absorption length; High-temperature testing; Ring-down time; OH concentration
Introduction

Quantitative measurement of substance concentration in the combustion field is necessary to understand the chemical reaction of combustion. As an important intermediate combustion product, OH plays a vital role in studying the chemical combustion reaction. Laser-induced fluorescence (LIF) has been used to measure the number density of OH particles[1]. However, it is difficult to achieve the quantitative measurement of OH concentration by the LIF technique, and the main reasons are constant calibration, quenching of excited particles, and low one-way absorption intensity. Chen Shuang's group[2] obtained the real OH fluorescence signal in experience by subtracting the difference between the original LIF signal and pure Rayleigh scattering signal to calibrate the undesired background from scattered laser light. However, the uncertainty of the obtained OH concentration is still as high as ± 25%. Among them, the largest error comes from the uncertainty of LIF measurements, the measured temperature, and OH concentration distribution at the edges. In addition, the most serious difficulty in achieving quantitative measurement for LIF is first defining the energy transfer of excited states such as the total impact quenching rate of electronically excited states, and the energy transfer of rotational and vibration[3].

As a direct absorption spectroscopy technique, cavityring-down spectroscopy (CRDS) has gained widespread attention for the quantitative measurement of substance concentration[4]. Compared with the LIF technique, the CRDS has the advantages of high absorption intensity without being affected by laser energy fluctuations and the increased length of the absorption path to improve test sensitivity[5, 6, 7]. CRDS can be briefly summarized as a multi-pass absorption technique whereby the sample is placed in a high-finesse cavity, and the intensity decay of the laser is detected at the output mirror when the laser traverses in the cavity. In 1994, Gerard Meijer et al.[8] applied the cavity ring-down spectroscopy technique to combustion diagnosis and measured the absorption spectrum of OH. In recent years, CRDS was also employed in microwave plasma-assisted combustion[9] to measure the absolute concentration of the ground state OH radical at the ignition region. In addition, CRDS was also suitable for the quantitative measurement of other combustion intermediate products, such as CH4[10], CN[11], NO[12], HCO[13], and CO[14]. Although the CRDS technique has been widely used, the analysis of the measured concentration error is relatively rare. At present, Tu Xiaobo et al.[15] have carried out concentration error analyses caused by experimental equipment such as laser linewidth and line-type, laser frequency stability, and the response of photomultiplier tubes. However, by analyzing the CRDS theories, we find that the precise measurement of experimental parameters will also cause great errors in CRDS concentration measurement, such as replacing effective absorption length with burner surface diameter[15], the measured temperature errors, and the influence of flame for cavity ring-down time.

In this paper, the quantitative measurement of OH concentration is carried out by a pulsed CRDS technique on a McKenna burner with premixed CH4/air gases. Due to heat radiation and heat transfer[16], it is difficult for the thermocouple to achieve accurate temperature measurement at room temperature, so the high-precision CARS technique is used to measure the real temperature for the high-temperature flame. The PLIF technique obtains the flame structure distribution, and then the effective absorption length at different heights from the burner surface is measured. The P1(2) absorption line spectrum of the electronic transition band of OH A2Σ +-X2Π (0, 0) of OH is selected to build a pulsed CRDS experimental device with the 308.6 nm laser wavelength to measure OH concentration. By analyzing the absorption spectrum theories and using the accurate experiment measurement, we realize the precise and quantitative measurement of OH concentration on the flat flame burner.

1 Theory of CRDS

The ring-down time of the optical cavity is an important parameter for CRDS, and its expression is as follows[17].

τ=Lc(1⁃R+αl+ξ)(1)

where L is the cavity length of the optical cavity, c is the speed of light, R is the reflectivity of the cavity mirror, α is the absorption coefficient of the sample, l is the absorption length, ξ is the additional loss of the optical cavity.

When the optical cavity is empty (without flame), the ring-down time τ 0 can be expressed as

τ0=Lc(1⁃R+ξ)(2)

By substituting Eq.(2) into Eq.(1), the absorption coefficient expression of the sample can be obtained.

αOH=Lcl1τ-1τ0(3)

It can be seen from Eq.(3) that the sample absorption coefficient is mainly determined by the ring-down time and absorption length and is not affected by the laser intensity[5, 18].

In addition, the absorption coefficient of combustion products can be expressed as[15]

αOH=nOHfBhνηB12c(4)

Where fB represents the Boltzmann coefficient corresponding to the ground state of combustion products, h is the Planck constant, ν is laser frequency, η is the overlap factor, and B12 is the absorption coefficient of Einstein.

Eq.(3) is substituted into Eq.(4), and the concentration of the combustion product OH can be expressed as

nOH=LfBhνB12ηl1τ-1τ0(5)

It can be seen from Eq.(5) that the main factors affecting OH concentration are absorption length, decay time, and Boltzmann coefficient. However, the decay time is also affected by the additional loss of the optical cavity, so keeping the consistency of the combustion state can effectively eliminate the error caused by the additional loss. The LIFBASE database finds the Boltzmann coefficient fB corresponding to each temperature under the steady-state condition. As shown in Fig.1, the absorption intensity of OH gradually decreases with the increase in temperature, which can indicate that temperature impacts the accuracy of OH concentration measurement.

Fig.1 The absorption intensity of OH at different temperatures

2 Experimental Setup

In the complex spectral cackground, the absorption wavelength of OH is selected to avoid the highly overlapping absorption lines in the spectral bandwidth as much as possible, which can improve the signal-to-noise ratio and reduce the interference of adjacent spectral lines. The laser linewidth in the experiment is 0.3 cm-1, so the P1(2) absorption line in the electron transition band of A2Σ +-X2Π (0, 0) of OH is selected as the absorption wavelength of OH.

The pulsed CRDS experimental device is shown in Fig.2. The laser system consists of a solid laser, a dye laser, and a frequency-doubling device. The laser system outputs a 308.6 nm UV laser with a pulse width of 10 ns, a repetition frequency of 10 Hz, and a pulse energy of 3 mJ. The plane mirror M1 fully reflects the 617.2 nm laser and transmits the 308.6 nm laser. The wavelength meter monitors the reflected 617.2 nm laser to ensure that the wavelength of the 308.6 nm laser can transmit through M1 without shifting. The transmitter 308.6 nm UV laser first passes through the pinhole to filter stray light and then enters the ring-down cavity. The two mirrors of the ring-down cavity (M4 and M5) use concave mirrors with a curvatuse radius of -6 000 mm and have 99.7% reflectance near 308 nm. The cavity length is 2.7 m to avoid interference between two adjacent pulses in the cavity. A filter plate (M6) is placed behind the optical resonator, which filters the background noise and only lets the light around 308 nm pass through. The filtered ring-down signal is received by a photomultiplier tube, and then the data is collected by a high-speed Oscilloscope.

Fig.2 A pulsed CRDS experimental device

In the experiment, a flowmeter is used to control the flow rates of CH4/air/N2, N2 is used to protect the flame stability, and the premixed CH4/air is completed before reaching the flat flame burner. The parameters of experimental cases are shown in Table 1. Five cases with different equivalence ratios are selected in the experiment, which can realize high-temperature combustion[19]. Under each case, the interval of 3 mm height is performed from close to the burner surface, and a total of 9 groups of ring-down signal data are measured.

Table 1 Parameters of testing cases
3 Results and Discussion
3.1 Temperature measured by CARS

The temperature must be precisely measured to get the precise Boltzmann fraction fB. In the combustion environment of case 1, the CARS technique and thermocouple are used to measure the temperature of different heights at the same step, and the temperature difference and the relative error of fB are shown in Fig.3. As shown in Fig.3, the larger the temperature difference between CARS and the thermocouple, the larger the relative error of fB. With the increased distance from the burner surface, the temperature difference decreases gradually. When the distance from the burner surface is 6 mm, the temperature difference between the measuring point of CARS and the thermocouple is the highest, and the relative error of fB can reach 45%, which indicates that the deviation of the measured temperature by the thermocouple in the high-temperature environment is large. The thermocouple cannot meet the requirements of temperature measurement.

Fig.3 The temperature difference between CARS and the thermocouple (red dot) and fB relative error (blue dot) at different heights for case 1

To illustrate the accuracy of temperature measurement of the CARS system in the laboratory[19], five cases in the DLR[20] (Deutsches Zentrum fur Luft-und Raumfahrt) are selected and measured for comparison. The results of the measured temperature by CARS are shown in Fig.4(a), and the results indicate that the measured temperature by CARS in the laboratory is completely consistent with those in the literature. Therefore, the CARS system is used to measure the temperature of the remaining casesat different heights, and the temperature results are shown in Fig.4(b).

Fig.4 The measured temperatures by CARS
(a): The relationship between DLR literature temperature and CARS temperature; (b): CARS temperatures of different cases

3.2 Effective absorption length measured by PLIF

To accurately measure the effective absorption length of OH, the PLIF technique is first used to obtain the flame structure under different cases, and then the absorption lengths of OH at different heights are measured. As shown in Fig.5(a), the PLIF technique is used to obtain the flame structure of case 1, and the red line in Fig.5(a) is the effective absorption length of OH when the height from the furnace surface is 15 mm. It can be seen from Fig.5(b) that the effective absorption length of OH decreases with the increase of distance from the burner surface. The relative error of absorption length increases with height increasing. If the effective absorption length is replaced by the furnace face diameter, it will cause a 7.1%~39.5% relative error, and the higher the height, the greater the error. Therefore, the effective absorption length of different cases must be accurately measured by the PLIF technique.

Fig.5 (a) The measured active absorption length (red line) by PLIF at the height of 15 mm; (b) Active absorption lengths and relative errors at different heights for case 1

Figure 6 shows the measured effective absorption lengths by the PLIF technique at different heights from the burner surface for the remaining cases. As can be seen from case 4 in Fig.6, when the gas flow rate is very high, only a part of the effective absorption length near the burner surface is equal to the diameter of the burner surface.

Fig.6 Active absorption lengthsindifferent cases

3.3 OH concentration measured by CRDS

When the optical cavity is empty, the signal of the ring-down cavity is shown in the upper right corner of Fig.7(a). In Fig.7(a), the round-trip propagation time of the optical pulse in the cavity is 18 ns, which is larger than the laser pulse width of 10 ns, and the interference of two adjacent pulses in the cavity can be effectively avoided. As shown in Fig.7(b), the ring-down time τ 0 of the empty cavity is 2.33 μ s by selecting the maximum value of the ring-down signal and e-index fitting.

Fig.7 Cavity ring-down signal without a flame in the cavity
(a): Raw data; (b): Signal fitting

To verify the influence withouta flame in the cavity for the ring-down time τ 0, it is also necessary to measure τ 0 when there is a flame in the optical cavity. When the flat flame burner is ignited in the cavity, and the laser wavelength is adjusted to the non-absorbing wavelength of OH, the ring-down time τ 0 of case 1 is obtained at different heights from the burner surface, as shown in red star in Fig.8(a).It can be seen from Fig.8 (a) that τ 0 of the empty cavity is greater than that of the flame inthe cavity, which indicates that the flame in the cavity will affect the value of τ 0 by the additional loss of the optical cavity. As shown in Fig.8(b), the relative error of cavity ring-down time τ 0 at different heights increases by 12.8%~21.6% compared with the ring-down time with flame in the combustion environment for case 1. It is mainly due to the Rayleigh scattering[15] caused by impurity particles in the flame combustion process, which causes a change in the additional loss ξ . Moreover, it can be seen from Eq.(2) that the additional loss ξ will affect the value of the ring-down time τ 0, but the ring-down time τ 0 of the empty cavity ignores the loss caused by the flame impurity particles.

Fig.8 (a) The influence for τ 0 with and without a flame in the cavity, (b) τ 0 relative error for case 1

The overlap factor η is 2.188 cm and B12 is 2.278× 109 m2· J-1· s-1, which can be obtained by checking the LIFBASE database. Then the OH concentration will be obtained by substituting the above parameters into Eq. (5). As shown in Fig.9, the OH concentration at different height positions is obtained by accurate measurement of experimental parameters in the combustion environment of case 1. The OH concentration increases by 35.6%~47.9% compared with the uncorrected one.

Fig.9 The concentration of OH and relative error for case 1

The OH concentration and fitting curves at different cases are shown in Fig.10. As can be seen from Fig.10, with the increase of heights from the burner surface, the concentration of OH gradually decreases, which is the same trend as the tested results in the literature[15, 21]. It is found that the concentration of OH decreases exponentially with the increase of heights from the burner surface by fitting the curve. By comparing cases 1, 2, 3, and 4 at the same combustion height, we find that the concentration of OH increases with the increase of the equivalent ratio under the condition of oxygen-rich combustion. The comparison of cases 2 and 5 shows that the OH concentration in the oxygen-rich state is higher than that in the low-oxygen state when the CH4 flow rate remains constant.

Fig.10 OH concentrations and curve fittings at different cases

4 Conclusion

The experimental results show that CARS, PLIF, and the pulsed CRDS have successfully measured the OH concentration in a flat flame burner with the premixed CH4/air. A set of the pulsed CRDS experimental device with the 308.6 nm laser wavelength is constructed by selecting the P1(2) absorption line spectrum of the electronic transition band OH A2Σ +-X2Π (0, 0). By analyzing the spectrum theory, we find that the experimental parameters that affect the precise measurement of concentration are the effective absorption length of OH, temperature, and decay time. Planar laser-induced fluorescence (PLIF) is used to measure the changed effective absorption length of the flame structure. Coherent anti-Stokes Raman scattering (CARS) is used to measure the temperature field of the high-temperature flame accurately. The pulsed CRDS is used to measure the ring-down time by igniting the flame inthe optical cavity, which is affected by the additional loss. When the premixed CH4 (1.1 L· min-1) and air (15 L· min-1) are burned on the flat flame burner, and the measured height from the burner surface is 6 mm, the measured accuracy of the effective absorption length by the PLIF technique is 7.1% higher than that by directly choosing the diameter of the burner surface as the absorption length, the measured accuracy of thetemperature by CARS technique is 45% higher than that measured by a thermocouple at room temperature, the measured precision of the cavity ring-down time is improved by 21.6% than that measured ring-down time of the empty cavity when the flame is ignited in the cavity, and non-OH absorption wavelength is selected. By using a combination of the above technologies to achieve precise measuring experiment parameters, we find that the number density of OH molecules (3.59× 1013 molecules· cm-3) can reach the maximum value when the height from the burner surface is 6 mm, and the precision of OH concentration is 35.6% higher than that of the unmodified OH concentration. Under the different equivalence ratios (Φ =0.7~1.1), with the increase of the heights from the burner surface, the number of OH particles gradually decreases, and the curve fitting shows that the OH concentration decreases in an e-exponential decay. Under the condition of oxygen-rich combustion, the concentration of OH at the same height increases with the increasing equivalent ratios. When the CH4 flow rate remains constant, the OH concentration in the oxygen-rich combustion condition will be higher than in the low-oxygen combustion condition.The precise measurement of OH concentration is improved by combining the CRDS-CARS-PLIF multi-technique, which can provide strong data support for chemical combustion analysis.

参考文献
[1] Maxime B, Gilles C, Jérôme Y, et al. Proceedings of the Combustion Institute, 2021, 38: 1851. [本文引用:1]
[2] Chen Shuang, Su Tie, Li Zhongshan, et al. Chinese Physics B, 2022, 31: 034702. [本文引用:1]
[3] Fuchs H, Dorn H P, Bachner M, et al. Copernicus Publications, 2012, 2: 1611. [本文引用:1]
[4] Ning Kai, Hou Lei, Fan Songtao, et al. Chinese Physics Letters, 2020, 37: 064202. [本文引用:1]
[5] Cotterell M I, Knight J W, Reid J P, et al. The Journal of Physical Chemistry A, 2022, 126: 2619. [本文引用:2]
[6] Maithani S, Mand al S, Maity A, et al. Analyst, 2018, 143: 2109. [本文引用:1]
[7] Lukashevskaya A A, Kassi S, Campargue A, et al. Journal of Quantitative Spectroscopy and Radiative Transfer, 2017, 200: 17. [本文引用:1]
[8] Gerard M, Maarten G H B, Rienk T J, et al. Chemical Physics Letters, 1994, 217: 112. [本文引用:1]
[9] Che F, Wang Chuji. IEEE Transactions on Plasma Science, 2020, 48: 2646. [本文引用:1]
[10] Wei Qianhe, Li Bincheng, Wang Jing, et al. Atmosphere, 2021, 12: 221. [本文引用:1]
[11] Zhou Sheng, Han Yanling, Li Bincheng. Applied Physics B, 2018, 124: 27. [本文引用:1]
[12] Song Yu, Lorena M, Nicolas V, et al. Proceedings of the Combustion Institute, 2018, 37: 667. [本文引用:1]
[13] Niels C M, Paul N N. Analytical Letters, 2020, 54: 1. [本文引用:1]
[14] Louviot M, Suas-David N, Boudon V, et al. Journal of Chemical Physics, 2015, 124: 21. [本文引用:1]
[15] TU Xiao-bo, CHEN Shuang, SU Tie, et al(涂晓波, 陈爽, 苏铁, 等). Infrared and Laser Engineering(红外与激光工程), 2017, 46: 239002. [本文引用:5]
[16] CHEN Yong-qiang, CUI Xin-yuan, WU Qin, et al(陈永强, 崔馨元, 吴勤, 等). Metrology & Measurement Technique(计量与测试技术), 2018, 45: 2. [本文引用:1]
[17] Lisak Daniel, Charczun Dominik, Nishiyama Akiko, et al. Scientific Reports, 2022, 12: 2377. [本文引用:1]
[18] Alali H, Gong Zhiying, Videen G, et al. Journal of Quantitative Spectroscopy and Radiative Transfer, 2020, 255: 107249. [本文引用:1]
[19] YANG Wen-bin, QI Xin-hua, WANG Lin-sen, et al(杨文斌, 齐新华, 王林森, 等). Physics of Gases(气体物理), 2020, 5: 6. [本文引用:2]
[20] Weigand P, Rainer L, Wolfgang M. DLR—Institute of Combustion Technology, 2003, 27: 424. [本文引用:1]
[21] Arnold A, Bombach R, Käppeli B, et al. Applied Physics B: Lasers and Optics, 1997, 64: 579. [本文引用:1]