Guided Wave-based Corrosion Damage Assessment of Pressure-resistant Shells for Underwater Energy Supply Equipment

The pressure-resistant shell of underwater energy supply equipment is susceptible to corrosion damage due to the seawater pressure and corrosive media, which can lead to serious safety incidents. Based on the guided wave damage detection technique, guided wave signals are generated and received using 'one-shot-one-receiver' piezoelectric sensors positioned on the inner surface. Blind holes with radii of 3, 4, 5, 6, 7, 8, 9, 10, 11, and 12 mm are created at the center of the sensors on the outer surface to investigate the sensitivity of guided waves to varying degrees of corrosion damage in pressure-resistant shells. Using the Hilbert transform to extract the peak of the direct wave envelope as an indicator of damage, it was observed that the peak amplitude increased in correlation with the extent of corrosion damage. The test results show that the method effectively assesses the degree of corrosion damage to the pressure-resistant shell structure of underwater energy supply equipment.