Civil Engineering Reference
In-Depth Information
−
10
Test: Bare
Test: with attached foam
−
20
−
30
−
40
−
50
60
−
70
−
0
100
200
300
400
500
600
700
800
900
Frequency (Hz)
Figure 13.10
Effect of the foam layer on the space averaged quadratic velocity of the
plate.
−
25
Test
Prediction: FEM
−
30
−
35
−
40
−
45
−
50
−
55
−
60
−
65
−
70
0
100
200
300
400
500
600
700
800
900
Frequency (Hz)
Figure 13.11
Comparison between measured and predicted space averaged quadratic
velocity of the plate with attached foam layer.
Figure 13.12 presents the contribution to the dissipated power within the foam panel
system by the different dissipation mechanisms
tot
=
diss
_
plate
+
diss
_
foam
diss
_
foam
=
struct
+
viscous
+
thermal
(13.73)
The different dissipated powers are computed numerically using the expressions pre-
sented in Section 13.7. Radiation damping is neglected as explained in the previous
