Synthetic dataset of a full wavefield representing the propagation of Lamb waves and their interactions with delaminations

The dataset contains 475 simulated cases of full wavefield of Lamb waves propagation in a plate made of carbon fibre reinforced plastic (CFRP). The simulated 475 cases represent delaminations with different locations, shapes, and sizes. The following random factors were simulated in each case:

• delamination geometrical size (ellipse minor and major axis randomly selected from the interval [10 mm, 40 mm],
• delamination angle (randomly selected from the interval [0◦ , 180◦]),
• coordinates of the centre of delamination (randomly selected from the interval [0 mm, 250 mm − δ] and [250 mm + δ, 500 mm], where δ = 10 mm).

The guided waves were excited at the centre of the plate by applying equivalent piezoelectric forces. The excitation was in the form of toneburst sine signal modulated by the Hann window. The carrier frequency is assumed 50 kHz, and the modulation frequency is 10 kHz. The total wave propagation time was set to 0.75 ms so that the guided wave can propagate to plate edges and back to the actuator twice. The number of time integration steps was 150000 which was selected for the stability of the central difference scheme.

The material is a typical cross-ply CFRP laminate. The stacking sequence [0/90]₄ was used in the model. The properties of a single-ply were as follows [GPa]: C₁₁ = 52.55, C₁₂ = 6.51, C₂₂ = 51.83, C₄₄ = 2.93, C₅₅ = 2.92, C₆₆ = 3.81. The assumed mass density was 1522.4 kg/m3. These properties were selected so that simulated numerically wave front patterns and wavelengths are similar to the wavefields measured by SLDV on CFRP specimens used later on for testing the developed methods for delamination identification. The shortest wavelength of propagating A0 Lamb wave mode was 21.2 mm for numerical simulations and 19.5 mm for experimental measurements.

In each delamination case, 512 frames were generated to visualise the propagation of Lamb waves and their interactions and reflections from the delamination and edges.
The numerically generated dataset resembles the velocity measurements acquired by the scanning laser Doppler vibrometer (SLDV) at the bottom surface of the plate of dimensions 500×500 mm.

The uploaded dataset contains two ZIP files:

1.  The first file contains 475 folders regarding all cases of different delaminations and their interaction with Lamb waves. In each case, there are 512 images in PNG format representing the propagation of guided waves.
2.  The second file contains:
   • 475 images in PNG format representing the ground truth of the delaminations.
   • CSV file contains all info regarding delaminations.