Eddy current analysis for ECT of a conductor with a conductive crack by Boundary Element Method

We study how to solve eddy currents induced in a conductor with a conductive crack in order to apply to the eddy current testing (ECT). The eddy current is formulated by boundary integral equations whose unknowns are the surface electric and magnetic currents. When the skin depth is thick, computational error is increased in obtaining electromagnetic fields near the edge of the crack especially in the case of the conductive crack, and so we derive another integral equations by introducing a loop magnetic current on the crack surface. So as to check the validity of the proposed approach, we solve a typical ECT problem and compare the computed results with those by FEM.