Fast Technique for Lorentz Force Calculations in Non-Destructive Testing Applications

The primary aim of this paper is to present new 2-D/3-D numerical technique providing fast calculations of Lorentz forces acting on a permanent magnet moving relatively to a solid electrically conducting object. This specific field configuration represents a typical problem arising in novel non-destructive testing and evaluation technique known as the Lorentz force eddy-current testing (LET). The proposed technique, referred to as the weak reaction approach (WRA) is based on several model simplifications, which, in the limits of low magnetic Reynolds numbers, allow considerable reduction of the simulation time while maintaining the accuracy of the solution. For evaluation of the computational requirements and verification of the obtained results, the well-established sliding mesh technique is used. Finally, the presented WRA is applied to various parametric studies in form of defect imaging, which can throw light on possible reconstruction and localization of defects by solving an inverse LET problem.