Two-line atomic fluorescence as a temperature probe for highly sooting flames.

We investigate the applicability of two-line atomic fluorescence (TLAF) from seeded indium atoms for temperature measurements in highly sooting flames. The results show that TLAF holds promise for two-dimensional temperature measurements in sooting and fuel-rich flames under conditions in which other thermometry techniques fail, a result that is attributed to the superior characteristics of the indium atomization process. Furthermore, no native species was found to interfere spectrally with the detected TLAF wavelengths. Advantages of and problems with the technique are discussed.