Civil Engineering Reference
In-Depth Information
Table 12.3
The parameters of the orthotropic panel.
Parameters
Material from
Leppington parameters
2
.
0237
×
10
12
Young's modulus along direction 1 E
1
(Pa)
3
.
1375
×
10
13
Young's modulus along direction 2 E
2
(Pa)
8
.
8879
×
10
11
Shear modulus in directions 1,2 G
12
(Pa)
8
.
8879
×
10
11
Shear modulus in direction 2,3 G
23
(Pa)
8
.
8879
×
10
11
Shear modulus in direction 1,3 G
13
(Pa)
Poisson's ratio in direction 1,2
ν
12
0.028
Poisson's ratio in direction 2,3
ν
23
0.434
Poisson's ratio in direction 1,3
ν
13
0.0
Mass density of the material
ρ
(Kg/m
3
)
9740
Structural loss factor of the material
η
0.01
35
30
25
20
15
Test: Leppington
et al
. (2002)
Prediction: Leppington
et al
. (2002)
Prediction: FTMM
10
1000 2000 3000 4000 5000 6000 7000
8000
9000
10000
Frequency (Hz)
Figure 12.6
Transmission loss of a composite panel; experimental data taken from
Leppington
et al
. (2002).
=
4
.
87 kg/m
2
;
η
D
22
=
330
.
84 N;
m
=
0
.
01. Figure 12.6 shows the comparison between
the FTMM, experimental results and the analytical model presented by Leppington
et al
. (2002). In the FTMM the panel is modelled as a thick orthotropic panel (the
model includes shear effects; Ghinet and Atalla, 2006). Excellent agreement is observed
between predictions and testing. In particular, the FTMM captures very well the mass
and critical frequency controlled regions of the panel.
Reverberant absorption coefficient of a foam
This example considers the prediction of the reverberant (sabine) absorption coefficient
of the foam presented in Table 12.1. The tests were conducted at the National Research
