João Marcos Rebello; Cesar Camerini; João Vicente Rocha; Maria Cristina Areiza
Resumo: The 2012 Eddy Current Benchmark Problem involves the inspection of an inconel pipe using an internal pancake coil situated with its axis perpendicular to the axis of the pipe. The experimental data were supported by the Benchmark Eddy Current 2012, as released by the World Federation of Non Destructive Evaluation Centers (WFNDEC). The software OPERA 3D and COMSOL were used by the authors to solve the proposed simulation problem. The simulated results were in good agreement with the experimental ones. However some simulated results exhibited a small variation in the impedance and electrical resistance between the base material and the region around the notch. The values of these changes were plotted as a function of the displacement of the sensor over the notch region. The calculations were made for frequencies of 25kHz to 200kHz. A good agreement was obtained at low frequency. However, the simulation at high frequencies presented differences, which can be attributed to the mesh refinement. The finite elements in both software should be adjusted to two regions: the change of the small notch region and its neighborhood. It is important to adjust the mesh size parameter to compensate the low skin depth inherent to eddy current testing at high frequencies.
