A Study of Frequency Mixing Approaches for Eddy Current Testing of Steam Generator Tubes

  • Jung, Hee-Jun (School of Mechanical Engineering, Sungkyunkwan University) ;
  • Song, Sung-Jin (School of Mechanical Engineering, Sungkyunkwan University) ;
  • Kim, Chang-Hwan (School of Mechanical Engineering, Sungkyunkwan University) ;
  • Kim, Dea-Kwang (School of Mechanical Engineering, Sungkyunkwan University)
  • Published : 2009.12.30

Abstract

The multifrequency eddy current testing(ECT) have been proposed various frequency mixing algorithms. In this study, we compare these approaches to frequency mixing of ECT signals from steam generator tubes; time-domain optimization, discrete cosine transform-domain optimization. Specifically, in this study, two different frequency mixing algorithms, a time-domain optimization method and a discrete cosine transform(DCT) optimization method, are investigated using the experimental signals captured from the ASME standard tube. The DCT domain optimization method is computationally fast but produces larger amount of residue.

Keywords

References

  1. Arunchalam, K., Ramuhalli, P., Udpa, L. and Udpa, S (2002) Nonlinear Mixing Algorithms for Suppression of TSP Signals in Bobbin Coil Eddy Current Data, Review of Progress in Quantitative Nondestructive Evaluation., Vol. 21, pp. 631-638
  2. Chuang, S. (1997) Eddy Current Automatic Flaw Detection System for Heat Exchange Tubes in Steam Generators, Ph.D. Thesis, Iowa State University
  3. Lord, W. (1985) Electromagnetic Methods of Nondestructive Testing, Gordon and Breach Science Publishers, USA
  4. Pintiere, L. (1980) An Analysis of Multifrequency Eddy Current Mixing Parameters in Tubing Inspection, Nondestructive Evaluation in the Nuclear Industry, USA
  5. Stolte, J., Udpa, L. and Load, W. (1988) Multifrequency Eddy Current Testing of Steam Generator Tubes Using Optimal Affine Transform, Review of Progress in Quantitative Nondestructive Evaluation, Vol. 7A, pp. 821-830
  6. Avanindra (1997) Multifrequency Eddy Current Signal Analysis, M.S. Thesis, Iowa Stats University