| This work examines the application of Tunable Diode Laser Absorption Spectroscopy (TDLAS) to monitor high temperature CO 2 and O2. The selection of the optimum absorption line is the focus.; Calculated spectra of the Fermi triad of CO2 absorption bands were studied ranging from room temperature to 1500K. Based on the Voigt calculations, the R(32) transition of the nu1 + 2nu2 + nu3 band is proposed for combustion CO2 monitoring. The transition was experimentally recorded at various conditions and compared to Voigt profiles. It is proved to be a suitable transition for combustion CO2 detection.; Similarly, O2 spectra near 760nm were studied. The Voigt calculation shows that the transitions near the violet end of the b1 g+ (v'' = 0) ← X3 g- (v" = 0) band are potential for high temperature oxygen measuring. The follow-up experiments indicate that the RQ 25 transition offers a good balance of sensitivity and suppressed room temperature oxygen interference and is suggested for high temperature oxygen measurements. |
