De-Bonding Numerical Characterization and Detection in Aeronautic Multi-Element Spars.

Area of Science:

• Composite Materials Science
• Structural Health Monitoring
• Aerospace Engineering

Background:

• Composite structures require robust structural health monitoring (SHM) for safety and efficiency.
• Adhesion defects, such as glue deficiency or de-bonding, pose significant risks to composite joint integrity.
• Current maintenance often relies on scheduled checks, which can be inefficient and costly.

Purpose of the Study:

• To numerically characterize adhesive layer imperfections in a representative aircraft composite component.
• To extract information from various defect layouts and identify parameters describing defect peculiarities.
• To assess the macroscopic effects of these defects on structural behavior.

Main Methods:

• Numerical simulation of a multipart composite spar with bonded C-beams.
• A test campaign to analyze different defect configurations and their impact.
• Development and application of a proprietary code for defect detection and sizing.

Main Results:

• Identification of macroscopic evidence of defect effects, including localization and interference.
• Assessment of the impact of defects on the overall structural response.
• Correlation of numerical outcomes with estimations for defect presence and size.

Conclusions:

• Numerical characterization provides insights into adhesive layer imperfections in composite structures.
• The developed methodology shows potential for on-demand maintenance by detecting and sizing defects.
• This research contributes to the OPTICOMS project within the Clean Sky 2 Joint Technology Initiative.