Research on the Distribution of Gas Concentration of Two-Dimensional Reconstruction Based on Tunable Diode Laser Absorption Spectroscopy with Multispectral Absorption
ZHANG Li-fang, WANG Fei*, ZHANG Hai-dan, WU Qi, YAN Jian-hua, CEN Ke-fa
State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, China
Abstract：The two-dimensional concentration distribution was reconstructed by using algebraic iterative reconstruction algorithm. This paper mainly focused on the effects of multispectral H2O absorptions on condition that the laser beam was less and the temperature was known, i.e. the influence of temperature on spectral line-strength was not considered as to this concentration distribution. Based on ART algorithm, increased spectral lines and increased laser beam were compared under the same concentration model. Three H2O lines were selected to reconstruct two-dimensional distribution of non-uniform gas concentration, and these three transitions were selected within the external cavity diode laser turning range in the simulated system. The interested region was discretized to 10×10 grid points, and the temperature and concentration of the reconstruction model were not evenly distributed, so the unimodal distribution and bimodal distribution were used to describe the concentration distribution. The simulated system also calculated the effective utilization of laser beams and absorption lines. The results showed that the reconstruction quality quickly increased with increasing H2O absorption lines when the laser beams were very few, the increased absorption lines could get more spectral information related to the concentration. The increased laser beam is also effective to improve the accuracy of reconstruction results, but increasing the absorption lines can better reconstruct a two-dimensional concentration distribution. Improving the absorption lines can also effectively reduce the costs of the hardware and the complexity of the measurement system, which shows that the multispectral absorption lines are applicable to in-situ measurements.
张立芳，王 飞*，张海丹，吴 奇，严建华，岑可法 . 基于可调谐激光吸收光谱技术的多条吸收谱线重建气体浓度二维分布的研究 [J]. 光谱学与光谱分析, 2016, 36(11): 3485-3491.
ZHANG Li-fang, WANG Fei*, ZHANG Hai-dan, WU Qi, YAN Jian-hua, CEN Ke-fa . Research on the Distribution of Gas Concentration of Two-Dimensional Reconstruction Based on Tunable Diode Laser Absorption Spectroscopy with Multispectral Absorption . SPECTROSCOPY AND SPECTRAL ANALYSIS, 2016, 36(11): 3485-3491.
