Diode-laser based absorption spectroscopy can provide non-intrusive,
line-of-sight absolute measurements of multiple flow parameters.An accurate prediction of absorption spectra is essential for extracting
species concentrations and temperature in combustion gases using a
diode-laser based absorption spectroscopy. In the present study,high-resolution absorption spectra of CO2, CO, O2, H2O, and CH4 in the
near-infrared (IR) region are numerically simulated to understand their
spectral structures. The calculated spectra are compared with reported
experimental data under various temperature and pressure conditions to
assess the numerical models. Results demonstrate that the present
simulations can excellently reproduce the measured spectra, and the
developed numerical models can be utilized for future combustion emission
measurements.