Vibration suppression of composite plate and determination of settling time
The finite element mesh and patch geometries are similar. Laminate is covered with piezo-patches to the extent of 25 per cent, 50 per cent and 100 per cent in four different configurations as shown in Figure 22.2.
Figure 22.2: Different patch sizes and configurations of PVDF patch actuator
Free vibration response at the centre of the plate is obtained and plotted for different gain values to obtain settling time and damping ratio. Material properties of composite laminate and PVDF film are listed in Table 22.1.
Table 22.1 Numerical data used in analysis
Composite |
Glass-epoxy |
Stacking sequence |
0/0/0/0 |
Ply thickness |
0.5 mm |
Elastic modulus, E1 |
28.45 GPa |
Elastic modulus, E2 |
2.148 GPa |
Shear modulus, G12 |
1.032 GPa |
Poisson ratio, ν12 |
0.21 |
Density, ρ |
1670 kg/m3 |
Sensor |
PVDF film |
Elastic modulus, E1 = E2 |
2.0 GPa |
Shear modulus, G12 |
0.77 GPa |
Poisson's ratio, ν12 |
0.31 |
Density, ρ |
1800 kg/m3 |
Thickness of PVDF film (at top and bottom surface of laminate) |
0.1 mm |
Electro-mechanical coupling, d31 = d32 |
-2.74 x 10-12 C/N |
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