A Method for the Resolution of Simultaneous, Spatially Distinct Absorption Path Measurements Through the Use of Planar Tunable Diode Laser Absorption Spectroscopy

摘要

With the growth of the optical telecommunications field, Tunable Diode Laser Absorption Spectroscopy (TDLAS) has become a more viable and widely spread method for fluid diagnostics. Traditional TDLAS systems make measurements which are path integrated over a the line-of-sight of a single beam. This work introduces a novel method of taking simultaneous, spatially resolved measurements through the use of sheet forming optics to generate a laser plane instead of a beam. This plane is measured by an appropriate linear array camera (LAC), which makes spectroscopic measurements at each pixel of the array. This work introduces the LAC, noise characterization and initial issues and resolutions for these issues. Three demonstration measurements for the camera are also described: (a) in low pressure cell, (b) over a flat flame McKenna burner, and (c) in a Mach 2.75 wind tunnel. Finally, a Monte Carlo analysis is done on the current absorption features using the noise characteristics taken from the camera. The analysis is run over a range of pressures and temperatures to evaluate the range of validity for the measurements.