Page 236 - The Master Handbook Of Acoustics
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0.6
(Estimated)
Absorption coeff.
0.4
16" 0.2 Empty
45"
A 0
100 1,000 4,000
Frequency - Hz
0.6
(Estimated)
Absorption coeff.
0.4
12"
35" 0.2 Empty
B 0
100 1,000 4,000
Frequency - Hz
Filled with mineral wool
Absorption coeff. 0.4
10" 0.2
28" Empty
0
100 1,000 4,000
Frequency - Hz
C
Filled with mineral wool
Absorption coeff.
0.4
8" 0.2 Empty
20" Empty
D 0
100 1,000 4,000
Frequency - Hz
FIGURE 9-25
Measured absorption of polycylindrical diffusors of various chord and height dimen-
sions. In C and D, graphs are shown for both empty polys and for polys filled with min-
eral wool. In A and B only empty poly data are available; the broken lines are estimated
9
absorption when filled with mineral wool. (After Mankovsky. )
