Flame temperature diagnostics with water lines usingmid-infrared degenerate four-wave mixing
The feasibility of using degenerate four-wave mixing (DFWM) for hot gas thermometry in the mid-infrared spectral region is, for the first time, demonstrated by probing molecular ro-vibrational transitions of water. DFWM spectra of hot water were recorded in specially designed flames, providing a series of temperatures varying from 1000 to 1900 K and, the dramatic spectral structure variations were