A new approach for optimal design of Eddy Current Testing probes

The optimal design of ECT probes for advanced nondestructive inspection of steam generator tubing in nuclear power plants is studied in this paper. A new approach for probe design is proposed, on basis of both a simplified detectability analysis method and a ring current model newly developed by the authors. The new approach is incorporated in the optimization of pick-up arrangements as well as the corresponding excitation coils. Two designs of a potential ECT probe which may show high performance in practical applications are proposed finally. In addition, the ring current model and the simplified detectability analysis method are validated further for a conducting tube by comparing the magnetic field perturbation due to a crack and the S/N ratios evaluated by the present method and an FEM-BEM hybrid code respectively. Consequently, the validity of the new design approach and the high performance of the new probe designs are assured. © 1998 Plenum Publishing Corporation.