Modelling of a Differential Sensor in Eddy Current Non-destructive Evaluation

A. Rosell[1], and G. Persson[2]
[1]Volvo Aero Corporation, Trollhättan, Sweden
[2]Chalmers University of Technology, Göteborg, Sweden
Published in 2011

Interaction between the probe and a defect in eddy current non-destructive evaluation is studied. Evaluation of sensor signal response is the basis for the calculation. In this work a differential sensor is considered and the problem regarded here is problem 8 from the testing of electromagnetic analysis methods (TEAM) workshops.

The truncation, referring to the position of the outer boundaries of the finite element model, is evaluated in three dimensions (3D) by the use of an analysis in axial symmetry. The truncation can therefore be evaluated in an axisymmetric analysis which then can be used to assure a good result in 3D. The axisymmetric model is compared to an analytic model with good results.