Guided wave skew velocity correction in anisotropic laminates

Guided ultrasonic wave propagation in anisotropic structures results in directional dependency of velocity and wave skewing effects that can impact the accuracy of damage detection. Phase and group velocities of the A0 guided wave mode, propagating in a unidirectional carbon fiber reinforced laminate, were investigated exper-imentally and through finite element analysis. A correction for the significant offset in phase and group velocities due to wave skewing effects is illustrated for both point and short line sources, achieving good agreement with theoretical calculations assuming planar wave fronts. The influence of the line excitation length on velocity measurements is discussed.

Automated summary

Guided ultrasonic wave propagation in anisotropic structures, such as carbon fiber reinforced laminate, can cause directional dependency of velocity and wave skewing effects, affecting the accuracy of damage detection. This study experimentally and through finite element analysis investigated the phase and group velocities of A0 guided wave mode in a unidirectional carbon fiber reinforced laminate. A correction method for the significant offset in phase and group velocities due to wave skewing effects is proposed, achieving good agreement with theoretical calculations assuming planar wave fronts. The influence of the line excitation length on velocity measurements is also discussed.