ECT-signal calculation of cracks near fastener holes using an integral equation formalism with dedicated Green’s kernel

Abstract : Simulation of flaw detection by eddy-current testing requires the calculation of the eddy-current signal due to the presence of the flaw. In this paper, the surface integral method (SIM) is applied for the calculation of the crack signal in work-pieces composed of a conducting plate with a borehole. The adopted approach makes use of a Green’s operator that takes into account the effect of the borehole, thus the integral formalism is restricted to the crack surface only. The truncated region eigenfunction expansion (TREE) method is followed for the construction of the Green’s operator. Comparisons of the computed crack signal with numerical simulations carried out using a hybrid VIM-SIM approach and experimental results show excellent agreement.