Thermographic NDE advisory and guidance system

Analytical expressions for the thermal contrasts of defects, of varying diameters, depths and openings imaged using the flash and long pulse excitation methods, are presented. Included are: in-plane delaminations; adhesion defects and wall thinning of a fluid filled pipe. The theoretical predictions are shown to be in good agreement with experimental measurements. The analytical expressions have been incorporated in expert system-like software to enable the rapid evaluation of thermographic NDE for a specified application. The system computes the thermal contrast of user defined defects, for both excitation methods, and compares results with typical IR camera performance to assess the suitability of thermographic NDE.