THEORETICAL FITTING OF COMPUTER PROCESSED LASER RAMAN-SPECTRA FROM METHANE-AIR AND PROPANE-AIR FLAMES

A technique for rapid acquisition and computer processing of Raman signals is described for probing premixed laminar hydrocarbon-air flames using laser Raman spectroscopy. Temperatures can be determined to within plus or minus 50 degree K by fitting the observed N//2 spectrum at any point in the flame. Fits to the spectra of O//2, CO, H//2, and CO//2 are used to measure their mole fractions at the calculated N//2 temperature. For the remaining polyatomic species, the total area under the peak is the primary measure of their concentration.