LASER-INDUCED FLUORESCENCE THERMOMETRY AND CONCENTRATION MEASUREMENTSON NO-A-X(0-0) TRANSITIONS IN THE EXHAUST-GAS OF HIGH-PRESSURE CH4 AIR FLAMES/

Laser-Induced Fluorescence (LIF) excitation spectra in the NO A-X (0-0 ) band were used for temperature measurements in the postflame region of high-pressure CH4/air flames. To improve th quality of the measured spectra and to perform reliable line-shape measurements, the initial mixture was doped with approximately 400 ppm NO. At pressures up to 18 bar, excellent agreement was obtained between NO LIF temperatures and NARS/rotational Raman temperatures. Effective broadening coefficients were also determined in these flames. Problems with quantitative conc entration measurements of NO and single-pulse temperature measurements at high pressures are discussed.