A fast forward analysis scheme for nonlinear static electromagnetic problems

In this paper, a rapid forward scheme is proposed for simulation of the static magnetic flux leakage (MFL) signals arisen from an object of ferromagnetic material. By storing precalculated distribution data of the unflawed magnetic field into a database, the analysis region for solving the field perturbation due to a crack is greatly reduced by applying the feature that only the magnetic field in the vicinity of a crack can be significantly perturbed due to the presence of a crack. Having implemented the new scheme into an FEM-BEM hybrid code of the polarization method, the validity of the proposed method is proved by comparing numerical results of the fast forward solver with those obtained by the FEM-BEM polarization code.