H-2 CARS THERMOMETRY IN A FUEL-RICH, PREMIXED, LAMINAR CH4 AIR FLAME IN THE PRESSURE RANGE BETWEEN 5 AND 40 BAR/

To establish H-2 CARS thermometry at high pressure, accumulated H(2)Q- branch CARS spectra were recorded in the exhaust of a fuel-rich CH4/ai r flame at pressures between 5 and 40 bar. Temperatures were deduced b y fitting theoretical spectra to experimental data points. The Energy- Corrected Sudden (ECS) scaling law was employed to set up an empirical model for the calculation of H-2 linewidths in high-pressure hydrocar bon flames with H-2 as a minority species. Experimental H-2 CARS spect ra could be simulated very accurately with this model. The evaluated t emperatures agreed well with reference temperatures obtained by sponta neous rotational Raman scattering of N-2.