Study of Remote Field Eddy Current Technique by Use of Poynting Vector

Abstract

The remote field eddy current technique, a promising in-service non-destructive inspection method of ferromagnetic tubing, has been studied by use of poynting vector to indicate the flow of electromagnetic energy. The intensities of the energy flow as well as its direction inside and outside of the tube have been derived quantitatively, which can explain some unknown RFECT phenomena. The energy penetrating through the tube wall propagates outside along the tube and then penetrates again through the wall back into the tube inside. Thus, defects in the tubing can be detected by the detector located inside the tube about two tube diameters away from the exciter.