1994 Volume 43 Issue 495 Pages 1628-1633
A new effective three-dimensional boundary element method of analyzing electric field produced by localized corrosions has been developed to estimate the accuracy of SVET (Scanning Vibrating Electrode Technique). With decreasing height of the electrode probe from the surface of a sample in an attempt to improve the resolution of SVET, the electrode probe disturbs the electric field and the measuring error of the current distribution increases. It is, therefore, desirable that this error is corrected by numerical analysis considering the disturbance of the electrode probe. However the scale ratio of the whole vessel of the instrument to the measurement area is larger than a factor of 105, so that the conventional BEM has a difficulty in treating such a huge number of elements. In this study, at first the distribution of current density on the slender surface of a sample where current flows out was analyzed with the two-dimensional BEM and then a three-dimensional Boundary Element analysis was performed by considering the slender surface as a simple line-shape element which has the characteristics obtained by the first 2-D analysis. By using the proposed method, the number of elements and repetitive calculations due to scanning of electrode probe can be decreased. A few numerical examples are presented to demonstrate the practical applicability of the proposed method.