Acoustic emission localization in beams based on time reversed dispersion

Area of Science:

• Materials Science
• Structural Health Monitoring
• Non-Destructive Testing

Background:

• Traditional acoustic emission (AE) localization requires multiple sensors and arrival time difference analysis.
• Phase dispersion in elastic waves complicates traditional time-of-arrival (TOA) localization methods.
• Existing methods struggle with complex structures and anisotropic materials.

Purpose of the Study:

• To introduce a new AE source localization method using a single, unidirectional measurement.
• To overcome limitations of TOA methods by utilizing wave dispersion.
• To demonstrate the feasibility of localizing multiple AE sources in various structural configurations.

Main Methods:

• Utilizes the time reversal principle and the dispersive behavior of flexural wave modes.
• Combines experimental AE testing with numerical simulations.
• Sets measured and time-reversed displacement history as a boundary condition in simulations.
• Employs pencil lead breaks (ASTM E976) on aluminum and carbon fiber reinforced plastic beams.

Main Results:

• Successfully localized multiple AE sources with a single measurement point.
• Achieved accurate localization even in anisotropic materials and complex geometries (notches, cross-sectional changes).
• Demonstrated a relative error of less than 5% for AE source localization.

Conclusions:

• The proposed method offers a significant advancement for AE source detection and localization.
• It effectively uses wave dispersion, overcoming limitations of traditional TOA techniques.
• The method is robust and applicable to complex and anisotropic structural components.