Guided wave multi-frequency damage localization method in variable-thickness structures by one pair of sensors based...

Area of Science:

• Structural Health Monitoring
• Wave Propagation in Materials
• Non-Destructive Testing

Background:

• Variable thickness structures in aerospace and marine applications require extensive sensor networks for safety.
• Existing methods often necessitate a high density of sensors for accurate damage detection.

Purpose of the Study:

• To develop a novel guided wave localization method for variable thickness structures.
• To reduce sensor count in structural health monitoring systems.
• To leverage frequency-dependent velocity anisotropy for improved damage localization.

Main Methods:

• Utilized a guided wave multi-frequency localization technique.
• Exploited frequency-dependent velocity anisotropy caused by structural thickness variations.
• Analyzed the deviation of damage loci from elliptical shapes at different frequencies.

Main Results:

• Successfully located damage in a variable thickness steel plate using a single pair of sensors.
• Demonstrated that damage loci at different frequencies converge at the damage site.
• Verified improved localization accuracy compared to traditional sensor networks.

Conclusions:

• The multi-frequency guided wave method enables accurate damage localization in variable thickness structures with fewer sensors.
• This technique offers potential for lightweight monitoring systems, phased arrays, and enhanced imaging.
• Frequency-dependent velocity anisotropy is a key factor for precise damage identification in complex structures.