A model for predicting the properties of guided ultrasonic waves, and illustration of its application to NDT

The exploitation of guided waves is dependent on a good understanding of the properties of the possible wave modes for a target structure and measurand. The development of successful guided wave inspection methods invariably starts with a careful study of the wave modes for the structure, from which the best mode and frequency can be chosen, then the appropriate instrumentation developed. The complicated nature of the modes can itself be a benefit because potentially there are many features which can be sensitive to the measurand if exploited with knowledge. The research of the NDT group at Imperial College includes considerable interest in exploiting guided waves: this has been the motivation of the authors to develop a general purpose and versatile model to calculate ultrasonic guided wave properties. This paper presents a summary of the workings and capabilities of the model and some examples of its application