Composite materials are used in many advanced engineering applications because of high specific strength and stiffness. Their complex damage mechanisms and failure modes, however, are still not well-understood, thus challenging the application safety. Ultrasonic guided waves are promising structural health monitoring tools used to determine the operational safety of composite materials. In this article, a fully coupled numerical simulation model is used to study wave propagation and dispersion in composites under varying sensor locations, propagating orientations, excitation frequencies, and damage locations. The model is based on the local interaction simulation approaches/sharp interface model wherein output sensor signals are processed using the matching pursuit decomposition algorithm to study the signal features in the time–frequency domain. The changes in signals due to varying damage locations with respect to the through-thickness direction are studied under anti-symmetrical and symmetrical excitation scenarios. The results show that the signal from symmetric excitation is more sensitive to the damage location, while the signal from anti-symmetric excitation is less dispersive. It indicates that comprising effective feature extraction technique with the accurate physics-based numerical simulation model can be implemented to develop robust structural health monitoring framework for composites.
Numerical Simulation of Fatigue Crack Growth in Straight Lugs Equipped with Efficient Structural Health Monitoring