Scanned-wavelength-modulation spectroscopy near 2.5 mu m for H2O and temperature in a hydrocarbon-fueled scramjet combustor

作者：Goldenstein C S^*; Schultz I A; Spearrin R M; Jeffries J B; Hanson R K

来源：Applied Physics B: Lasers and Optics , 2014, 116(3): 717-727.

DOI：10.1007/s00340-013-5755-0

The design and demonstration of a two-color tunable diode laser sensor for measurements of temperature and H2O in an ethylene-fueled model scramjet combustor are presented. This sensor probes multiple H2O transitions in the fundamental vibration bands near 2.5 mu m that are up to 20 times stronger than those used by previous near-infrared H2O sensors. In addition, two design measures enabled high-fidelity measurements in the nonuniform flow field. (1) A recently developed calibration-free scanned-wavelength-modulation spectroscopy spectral-fitting strategy was used to infer the integrated absorbance of each transition without a priori knowledge of the absorption lineshape and (2) transitions with strengths that scale near-linearly with temperature were used to accurately determine the H2O column density and the H2O-weighted path-averaged temperature from the integrated absorbance of two transitions.

• 出版日期2014-9