Multilevel adaptive cross approximation for efficient modeling of 3D arbitrary shaped eddy current NDE problems

Microwave Eddy-Current Techniques for Quantitative NDE

The objective of this research program is to develop microwave scattering techniques for obtaining quantitative information about the characteristic dimensions of surface cracks in metals. Work carried out during the past year has emphasized experimental techniques. The use of an IF bridge and a nearfield dielectric probe to improve the sensitivity of our 100-GHz eddy-current measurement system...

Quantitative Analysis of Eddy Current NDE Data

A new method for analyzing eddy current inspection data is presented. The key concept behind this method is extraction and isolation of the sample response from the measured signal. The measured signal depends on many factors including, not only the characteristics of the probe itself, the sample material, the operation frequency, and the probe/sample geometry, but also the measurement instrume...

Analysis of multilevel methods for eddy current problems

In papers by Arnold, Falk, and Winther, and by Hiptmair, novel multigrid methods for discrete H(curl; Ω)-elliptic boundary value problems have been proposed. Such problems frequently occur in computational electromagnetism, particularly in the context of eddy current simulation. This paper focuses on the analysis of those nodal multilevel decompositions of the spaces of edge finite elements tha...

Adaptive cross approximation for ill-posed problems

Regularization approach for inverse problems in order to characterize defects by eddy current NDE

Usual NDE techniques do not produce estimates of the depth of a surface breaking defect when this depth is below 5 mm. We propose a method based on the regularization of inverse problems that allows one to characterize surface breaking defects from eddy current sensors measurements. This method is based on two steps: the first step is the estimation of the characteristics of the inspected mediu...