The Impact of Underwater Acoustic Noise Using Conventional and Shear-Horizontal Sensor in Acoustic Emission Testing

Nondestructive evaluation (NDE) techniques have made substantial progress, with a focus on sensors utilizing piezoelectric materials to detect guided waves in elongated structures. Guided waves, known for their efficient longdistance propagation characteristics, have traditionally been detected by conventional sensors designed for Lamb wave acoustic emission (AE) detection. However, underwater inspections, such as those in nuclear reactor vessel heads and internal lifting fixtures, introduce unique complexities. The presence of mechanical equipment in contact with water creates a complex acoustic environment, resulting in noise across a broad frequency range, significantly affecting conventional AE sensors designed for specific resonances. To address these challenges, shear-horizontal (SH) sensors, tailored for SH wave detection, can reduce the effect of environmental noise, resulting in cleaner and more reliable AE signals. Comparative studies between conventional and SH sensors confirm the superiority of SH sensors under the noise environment underwater. The paper presents numerical simulations, stress state analysis, attenuation studies, and AE tests, offering insights into the behavior and advantages of SH sensors in underwater inspections. These findings will help the continued development and application of SH sensors in critical industrial settings.