Modelling of Thermal Line Scanning for the Inspection of Delamination in Composites and Cracking in Metals
Abstract
This report describes a predictive capability, comprising analytical and numerical models, for the development and assessment of thermal line-scanning, an emerging non-destructive technique for the rapid inspection of aircraft struc- tural components. The models describe the two-dimensional heat diffusion process pertaining to the application of a thermal line source to an object moving at constant velocity. Relevant case studies are considered including delamination in a composite laminate and cracking in a metal plate. Numerical experiments show that for planar flaws aligned with the inspection surface the performance of thermal line scanning is broadly equivalent to that of con- ventional flash thermography. In contrast, for a surface-breaking crack, where the flaw plane is typically perpendicular to the scan direction, strong lateral heat flows induced by a narrow beam provide a superior basis for inspection. For problems that involve distributed cracking, like in the wing carry-through bulkhead in the F/A-18 aircraft, the technique could offer an advantage over more conventional methods of inspection.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 2004
- Accession Number
- ADA435630
Entities
People
- N. Rajic
Organizations
- Defence Science and Technology Group