TEMPERATURE-MEASUREMENT VIA OH SPECTRUM IN A FLAT C3H8 O-2 FLAME BY DEGENERATE 4-WAVE-MIXING/

The degenerate four-wave mixing (DFWM) spectra method was employed to measure the temperature in a premixed propane-oxygen flame via OH radi cals. The focus was to study the dependencies of the signal-to-noise r atio and linewidth of DFWM on the crossing angle. It was found that te mperature measurements via DFWM could be made with crossing angles up to 13 degrees. Also, the DFWM signals were detectable for a crossing a ngle up to 25 degrees with acceptable signal-to-noise ratio. The resul ts suggest that it is possible to use DFWM two-dimensional imaging as a realistic diagnostic technique.