Finite element model of natural crack in eddy current testing problem

Eddy current testing (ECT) is one of the nondestructive inspection techniques to detect cracks and eddy current analysis is important for ECT. However, it is difficult to model a natural crack in finite element method (FEM), because of the narrow gap and the complex shape. In this paper, a finite element model for the natural crack is proposed. The conductivity for the finite element model is expressed by a tensor. In the proposed finite element, the change in crack shape and contact condition are simulated by changing the coefficients of the conductivity tensor. The proposed model is applied to a conductor plate model with a crack and a coil. The computation results are compared with the computation results of an artificial crack model. The validity of the proposed method is shown by the computation results