A quantitative review of three flash thermography processing routines

This manuscript presents a quantitative review of three flash-thermography processing routines; thermal signal reconstruction TSR, dynamic thermal tomography DTT, and pulse phase thermography PPT imaging. The review employs the following criteria; reliability under different experimental settings (pulse and acquisition durations), and bulks anisotropy levels, in addition to each code depth inversion accuracy under different host material conditions. The Signal to Noise ratio SNR and the contrast signal decay are used to quantitatively assess each code performance. The review implements the flash thermography experiments in an analytical domain to manipulate the test scenarios in greater details using finite differencing calculations in explicit mode, for two bulks; steel alloy and an epoxy-graphite composite. The PPT is found to be least sensitive to anisotropy variations, while the signal time-delay in TSR is shown to be dependant on defectives aspect ratio and on not its depth.