Journal of Nondestructive Evaluation

, Volume 1, Issue 3, pp 183–189 | Cite as

The impedance of a single-turn coil near a conducting half space

  • Afroz J. M. Zaman
  • Stuart A. Long
  • C. Gerald Gardner


The change in complex impedance between an ideal one-turn circular coil located above and parallel to a conducting half space with respect to a similar isolated coil has been calculated. From this result, a series expansion of the integrand allows the solution to be approximated by terms expressed as complete elliptic integrals. Results have been calculated for the change in impedance as a function of the liftoff distance and the conductivity of the half space for a coil of representative radius.

Key words

eddy current impedance liftoff conductivity 


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Copyright information

© Plenum Publishing Corporation 1980

Authors and Affiliations

  • Afroz J. M. Zaman
    • 1
  • Stuart A. Long
    • 1
  • C. Gerald Gardner
    • 1
  1. 1.Department of Electrical EngineeringUniversity of HoustonHouston

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