基于可调谐半导体激光吸收光谱技术(TDLAS),设计了气体浓度二维分布重建系统。将单路可调谐激光分为24路,交叉穿过目标区域,得到24组直接吸收信号(DA),并采用代数迭代法(ART)计算得到目标区域气体浓度二维分布。搭建了二维气体浓度分布测量试验台,利用中心波长在1.653μm的DFB激光器作为光源,选取HITRAN数据库CH4的2v3带R(3)线作为计算谱线进行数值模拟和试验验证,并对重建结果进行了误差分析。结果表明重建系统能很好的实现气体二维浓度分布重建测量。
A gas concentration reconstruction system is designed based on tunable diode absorption spectroscopy (TDLAS). A single diode laser is split into 24 beams crossing the target region. The 24 direct absorption (DA) signals are used to calculate the two-dimensional gas concentration distributions in the target region via algebraic reconstruction technique (ART). A test stage is established and a DFB laser with the central wavelength 1. 653μm is chosen as the light source. The absorption transition R(3) in the second overtone band of methane is selected from a HITRAN database. Based on these considerations, a numerical simulation and a verifying test are conducted as well as the error analysis. The results show relatively great fidelity of the two-dimensional gas concentration distribution reconstruction.