Solving the Inverse Geometric Problem of Magnetostatics for Corrosion Defects

Resumo

A method is proposed for solving the inverse problem of magnetostatics. The method has been investigated for metal-loss defects located on the side of a ferromagnetic plate opposite to magnetic transducers, without imposing any conditions on defect shape. The method is illustrated by numerical simulation. The ferromagnetic plate is magnetized in the direction of the abscissa axis; the dependence of the magnetic induction of metal on the applied external magnetic field corresponds to the linear segment of the magnetization curve. This configuration of defects and magnetizing system is typical, for example, of in-tube inspection problems. The problem is solved for the two-dimensional linear case. The applicability limits of the method are considered. The defects were simulated and the direct problem was solved using the FEMM software package. The program for constructing lines of force and solving the inverse problem of reconstructing magnetic field components has been written in the Scilab package of applied mathematical programs.