Numerical Investigation of the Excitability of Zero Group Velocity Lamb Waves

We numerically investigate the excitability of Zero Group Velocity modes by pulsed laser excitation. Within the numerical sim- ulations we solved the coupled heat and wave equations using the finite difference method and studied the influence of the ratio of the laser spot diameter (D) to plate thickness (h). Transient and steady-state responses were obtained in the time domain. In the simulations we have studied the transient response of tungsten plates with Fourier-transforms. The obtained numerical results show how the ratio D/h influences the coupling of the excitation into the Zero Group Velocity modes.