PSI - Issue 45

Xianwen Hu et al. / Procedia Structural Integrity 45 (2023) 20–27 Hu, X., Liang, P., Ng, C.T., and Kotousov, A. / Structural Integrity Procedia 00 (2019) 000 – 000

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Fig. 3. Schematic Diagram of (a) 3D FEM; (b) the Excitation Area

Table 1 Linear material properties of aluminium in intact condition

Elastic Modulus (GPa)

Poisson Ratio

Density (Kg/m 3 )

69

0.33

2704

Table 2 Nonlinear material constants of aluminium in intact condition (Hu et al. 2022)

Lame’s Constants

Third Order Elastic Constants

λ (GPa)

μ (GPa)

l (GPa)

m (GPa)

n (GPa)

51.6

26.6

-252.2

-325

-351.2

The dynamic simulation was achieved by ABAQUS/Explicit (SIMULIA 2008). Figure 4 presents a snapshot of the simulated wavefields, and it schematically shows the propagation of low FTV ES 0 at the edge of the plate. It can be observed that most energy of ES 0 is concentrated near the edge surface in the propagation, which means it is feasible to detect and monitor the damages near the edge by using the edge as a waveguide.

Fig. 4. Schematic Diagram of ES 0 Propagation

Fig. 5. Comparison of Linear and Nonlinear FE Simulation Results

Figure 5 shows the comparison of linear (without subroutine) and nonlinear (with subroutine) FE simulated signals in the frequency domain. The linear FE result (labelled as a blue solid line) can be seen as a benchmark that does not consider material nonlinearity. The nonlinear FE result (labelled as a red dash-dot line) clearly indicates the generation of higher harmonics of ES 0 .