The CO formation as a result of the CO2 photodissociation at 230.08 nm was observed by using the two-photon laser-induced fluorescence (LIF) method. The measurements were performed in a propane–air combustion product flow and in mixtures of CO2 and O2. The temperature dependence of the fluorescence signal caused by CO molecules, produced in the photodissociation of CO2 molecules under the action of laser radiation at a wavelength of 230.08 nm, was measured at temperatures ranging from 1300 to 2000 K. It is shown that consideration of CO2 photodissociation under the action of the probing radiation is necessary when one applies the two-photon LIF method for the measurement of small CO concentrations in high-temperature gas mixtures containing CO2. As an example, a correction is given of the CO concentration profiles measured by the LIF method in the combustion product flow around a cooled metallic plate.
© 1998 Optical Society of America
(120.0120) Instrumentation, measurement, and metrology : Instrumentation, measurement, and metrology
(120.1740) Instrumentation, measurement, and metrology : Combustion diagnostics
(260.5130) Physical optics : Photochemistry
(300.2530) Spectroscopy : Fluorescence, laser-induced
Anatoli P. Nefedov, Vladimir A. Sinel’shchikov, Alexander D. Usachev, and Andrei V. Zobnin, "Photochemical Effect in Two-Photon Laser-Induced Fluorescence Detection of Carbon Monoxide in Hydrocarbon Flames," Appl. Opt. 37, 7729-7736 (1998)