[8A2] Improving CIVA simulation of PAUT inspection using experimental TCG calibration data

M McInnes1,2, R O’Leary1, A Gachagan1 and A Glover2
1University of Strathclyde, UK
2QinetiQ, UK 

In recent years, the NDT simulation package, CIVA, has been undergoing development to improve its capabilities of approximating defect response amplitudes acquired from ultrasonic phased array inspections. Implementation of a custom-made script to apply a Time Corrected Gain (TCG) calibration showed improved amplitude approximation, compared with the in-built CIVA function, albeit with poor correlation to experimental data. The custom script applied a TCG to an inspection simulation by calibrating all amplitude responses relative to the response of a Side Drilled Hole (SDH) at the designated depth. The amplitude responses of SDHs at various depth are acquired through a subsequent simulation, shown in Figure 1(a). The implemented approach aligns those responses with experimental data to achieve amplitude calibration at each co-ordinate of the inspection simulation, by referencing the calibration amplitude relative to its location. To extend the utility of the methodology, uncalibrated responses of the inspection and calibration simulations can be aligned by considering the difference in response amplitude between SDHs and Flat-Bottomed Holes (FBHs) as a platform.