Numerical approach to binary complementary Golay coded infrared thermal wave imaging

Abstract

A novel binary complementary (Golay) coded infrared thermal non destructive testing and evaluation approach is introduced for characterization of mild steel sample having flat bottom holes as defects. The resultant correlation results of these individual Golay complementary codes used to reconstruct a short duration high peak power compressed pulse to extract the subsurface features hidden inside the test sample. In this paper, a finite element method has been used to model a low carbon steel sample containing flat bottom holes as sub-surface defects located at different depths. Results show the depth scanning capabilities of the proposed Golay complementary coded excitation scheme as a promising testing and evaluation method to detect the subsurface defects with improved resolution and sensitivity.