Combustion Phenomena of High Temperature Air Combustion - High Temperature Air Combustion: From Energy Conservation to Pollution Reduction - page 117

1373

1323

1273

1223

1173

1123

1073

1023

973

10 8 5 3

Oxygen contents of air, %

FIGURE 2.81 Spray flame at 0.3 MPa of the spray pressure in the high temperature preheated
diluted air.

2.4.1.4 Discussions

2.4.1.4.1 Blowout of Flame
A flame burning at a small distance from the exit of a nozzle, that is, a lifted flame,
was formed and blew out as the in-furnace temperature decreased. It can be consid-
ered that the reason for the flame blowout is that, as the in-furnace temperature
decreases, the fuel droplets form a steam layer, which prevents the fuel droplets
from gaining enough energy to cause autoignition.
Furthermore, the blowout of the flame occurred at a higher temperature, with
higher air dilution rate. However, the curves shown in Figure 2.77 as a result of the
experiment may change depending on the flame to be formed and the structure of
the combustion device. If the autoignition temperature as a specific characteristic of