Ultrasonic guided waves in solid media have received a significant attention in Structural Health Monitoring and Non-destructive Testing in recent years. Elastic waves are used in NDT applications as a fast and sensitive method to examine structural components. Although damage detection using ultrasonic guided waves has been thoroughly studied, there are serious difficulties in practical implementations due to dispersive and multimodal nature of the signals. Consequently, a number of advanced signal processing techniques have to be applied to extract relevant waveform features that carry information on structural damage. An inevitable part of a monitoring system is a transducer that is used to excite and acquire waves. Properly tailored properties of the transducer can effectively simplify the damage detection procedure and increase its reliability. The aim of presented work is to provide a conceptual understanding of possibilities and limitations of a virtual model of a piezoelectric sensor and to optimize its structure for desired application. The study focuses on a selective excitation of a guided wave mode. Such an approach is beneficial in terms of damage detection applications as specific type of a wave can be used for a problem at hand. What is more, due to selective nature of ac- tuation, signal processing techniques employed for damage detection and evaluation are much simpler and robust.
doi: 10.12783/SHM2015/132