Finding a crack's position and its parameters on the basis of non-destructive testing, using eddy currents

Abstract

Purpose

The purpose of this paper is to find the geometry of a crack within a conductive plate and its parameters, on the basis of non-destructive testing, using eddy currents. The input data represents the measured values of magnetic flux density within the centre of the excitation coil.

Design/methodology/approach

The position of a crack can be determined by taking into consideration any change in the magnetic flux density between the measured points. The depth and width are determined through the use of a finite element model.

Findings

These calculations are the basis for determining a function that explains how magnetic flux density changes if the depth or width has changed. Jacobi's matrix is calculated using the determined functions’ analytical derivatives.

Originality/value

After wards, through the Newton-Raphson iterative procedure using the finite element method calculation results, the crack-depth and width can be obtained, this being one of the objectives in this paper. The suitability of the presented method was verified by the experimental example.

Citation

Jesenik, M., Hamler, A., Beković, M. and Trlep, M. (2014), "Finding a crack's position and its parameters on the basis of non-destructive testing, using eddy currents", COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, Vol. 33 No. 6, pp. 1978-1989. https://doi.org/10.1108/COMPEL-11-2013-0370