
324 Industrial Air Quality and Ventilation
© 2010 Taylor & Francis Group, LLC
The volume of evacuated air is calculated using the air balance formula
. (5.241)
The amount of air inow through leaky locations is determined using formula
F
P
= 065
2
2
.
. (5.242)
For the double-walled enclosing design described earlier, the leaking area is
determined using the formula
, (5.243)
0
15
10
0.2
0.4
0.6
0.8
FIGURE 5.61 Pressure drop in the enclosing structure as a function of centering ange
area: = single-walled enclosing structure; = double-walled enclosing structure (
S
1
, S
2
—cross-sectional areas of the enclosing structure and ...