Implementing ultrasonic guided wave mode control in hollow cylinders

Ultrasonic guided waves have been successfully applied in Non-Destructive Evaluation (NDE) and Structural Health Monitoring (SHM) of pipelines of various industries. Guided waves are complicated because of their dispersive nature and infinite number of propagating modes. Mode control is of great significance for application of guided waves. The classical Normal Mode Expansion (NME) method is adopted to analyze guided wave mode control in hollow cylinders by using time delay axial array transducers and time delay circular array transducers. Guided wave mode control can be implemented when the axial array transducers and circular array transducers are specially designed. The theoretical prediction is verified by finite element numerical evaluation.