Spectroscopic Methods and Visualization Applied to Combustion Diagnoses - Novel Combustion Concepts for Sustainable Energy Development - page 185

flame (a) is mainly due to molecular emissions of
radiation from thermal excited CH and C 2 molecules, while the pink color of the
fl

The blue color of the intact fl

flame with seeding is attributable to those from FeO and Fe [ref].
Figure 14 shows the LIF spectra of Fe atoms and FeO molecules in the fl ames

with seeding.
In this experiment, the rotational temperature of the ames were measured by

comparing temperature dependent LIF lines of OH, or two-line method of LIF.
Figure 15 shows the rotation temperature pro

fl

les under the different conditions of

equivalence ratio.
Figure 16 shows the pro les of redox index calculated from the LIF intensity

ratio of Fe/FeO.
It is clearly indicated from Fig. 15 that the temperature reaches maximum when
the equivalence ratio is unity. On the other hand, Fig. 16 demonstrates that the
redox index is highest

in the fuel-rich combustion fl ame, independent of the

temperature.

Fig. 14 LIF spectra of Fe atoms (upper) and FeO (lower) molecules in the acetylene/air premixed
combustion flames with chemical seeding