A Rigorous Model for Inverting Eddy-Current Data

  • H. A. Sabbagh
Part of the Review of Progress in Quantitative Nondestructive Evaluation book series


Inverse scattering models, of the type that are often used to invert eddy-current data, are inherently nonlinear, because they involve the product of two unknowns, the flaw conductivity, and the true electric field within the flaw. Computational inverse models, therefore, often linearize the problem by assuming that the electric field within the flaw is known a priori. In this paper we describe how conjugate gradients might be applied to solve the nonlinear problem. The model is developed for an anisotropic material such as graphite epoxy, and is based on a method-of-moment discretization of two coupled integral equations.


Conjugate Gradient Algorithm Pulse Function Summation Term Couple Integral Equation Exciting Coil 


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Copyright information

© Springer Science+Business Media New York 1990

Authors and Affiliations

  • H. A. Sabbagh
    • 1
  1. 1.Sabbagh Associates, Inc.BloomingtonUSA

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