Table 1 Material properties, geometrical parameters, acoustic properties, and simulation conditions.
Parameter | Outer fluid | Reinforcement (string 1, 2) | Reinforcement (ring 1, 2) | Outer shell (FGM) | Air gap | Middle core | Air gap | Inner shell | Inner fluid | |
|---|---|---|---|---|---|---|---|---|---|---|
Material | Air | Steel | Steel | Al-ZrO2 | Air | Polymeric foam | Air | Aluminum | Air | |
Ceramic | Metal | |||||||||
Density \(\left(\frac{\text{kg}}{{\text{m}}^{3}}\right)\) | 1.284 | 7800 | 7800 | 5700 | 2760 | 1.03 | 100 | 1.03 | 2760 | 1.284 |
Young’s modulus (Gpa) | – | 210 | 210 | 200 | 72 | – | – | – | 72 | – |
Poisson’s ratio | – | 0.3 | 0.3 | 0.3 | – | 0.125 | – | 0.3 | – | |
Sound speed (m/s) | 340 | – | – | – | 371 | – | 371 | – | 340 | |
Thickness (mm) | – | 1 | 1 | 2 | 2 | 10 | 2 | 0.5 | – | |
Average radius (m) | – | – | 1.2 | – | – | |||||
Incidence angle (degree) | ψ = 45° | – | – | – | – | – | – | |||
