INFRARED CAVITY RINGDOWN LASER-ABSORPTION SPECTROSCOPY (IR-CRLAS) IN LOW-PRESSURE FLAMES

We report the first application of Infrared Cavity Ringdown Laser Abso rption Spectroscopy (IR-CRLAS) as a diagnostic tool for combustion che mistry studies. The high sensitivity (10(-5) fractional absorption) an d generality of IR-CRLAS for combustion studies is demonstrated for lo w pressure laminar flames and is shown to be robust even in sooting en vironments with high temperature gradients. The ability to obtain (1-D ) spatially resolved spectra of both reactants and products within a n arrow spectral region is also demonstrated. In these initial flame stu dies, two information rich mid-infrared spectral regions are probed at Doppler-limited resolution, centered about 1.5 mu m and 3.3 mu m.