Boundary element analysis of galvanic corrosion of long structure
- buried in soil with gradient electrical conductivity -
Aoki Shigeru; Takahashi Toru; Uragou Masataka; Amaya Kenji; Nishikawa Akinobu
Abstract:A new boundary element method for analyzing the galvanic corrosion of a long underground structure such as a pipeline and an oil well casing was developed. A long underground structure is often buried in soil with non-uniform electric conductivity. In case where the conductivity change is distinct, the conventional multi-region method is useful, while it gives an unrealistic solution with discontinuous jumps for gradual change of conductivity. To overcome the difficulty, the fundamental solution for a field with linear change of conductivity was introduced by using the Fourier transform technique, and the polarization characteristics were formulated to express its continuous change. A few example problems were solved with this method to demonstrate its applicability and usefulness. Key Words:galvanic corrosion, boundary element method, long underground structure, gradual change of electrical conductivity, fundamental solution, polarization curve, cathodic protection