
212 Oxygen-Enhanced Combustion
gases, the net radiant heat transfer from one surface to
another can be calculated from
qAFTTAFTT
12 1121
4
2
4
2211
4
2
4
⇔→ →
=−
(10.30)
where q
1⇔2
is the net energy transferred between sur-
faces 1 and 2, F
i→j
is the view factor or radiation shape
factor which is the diffuse radiation leaving surface i
and received at surface j and,
(10.31)
due to the reciprocity theory. Equations, charts, tables,
and graphs of radiation view factors are available else-
where.
55,59
An example will be given to illustrate this
type of analysis. The view factor between two identical,
TABLE 10.3
Normal Total Emissivities ...