Study of eddy currents non destructive testing system in riveted assemblies

In order to optimize eddy current sensors, we have to simulate electromagnetic phenomena to predict sensors' response. 2D and 3D codes can be used but what kind of result can be expected from each of these codes? In this paper, performances of 3D formulations are tested using FEM package Flux3d, Adapted coupled formulations and boundary conditions are used to study eddy currents perturbation by flaws in aircraft riveted assemblies. Physical informations about the influence of flaw depth are obtained. The 3D calculations allow us to choose the most adapted measurement quantity and to define the position of the measurement sensors. Then, for optimizing the sensor, 2D FEM package Fissure is used taking into account the 3D results.