Combustion Phenomena of High Temperature Air Combustion - High Temperature Air Combustion: From Energy Conservation to Pollution Reduction - page 116

1050 C 1000 C 950 C

FIGURE 2.79 Changes of the flame form.

5% 10%

Oxygen Content

FIGURE 2.80 Changes of the flame form by oxygen content (left: 5%, right: 10%).

and the oxygen content less than 5%, the external appearance of the flame changed
greatly. Figure 2.80 shows changes of the flame form according to the oxygen content
at 1000˚C of in-furnace temperature.
As shown in the figure, turbulence scarcely appears in the flame, and the flame
is nonluminous. However, if the oxygen content is higher, the flame form changes
with time. The causes for this phenomenon might be due to turbulence of the high
temperature airflow, a slight change of the spray in a short time, or due to turbulence
caused by an uneven generation of the combustion at some local regions. However,
these possible causes have not been investigated in the present experiment.