Fast boundary element method based on a 3D pipe model for analyzing cathodic protection
LIU Liqi, WANG Haitao
Key Laboratory of Advanced Reactor Engineering and Safety of the Ministry of Education, Collaborative Innovation Center of Advanced Nuclear Energy Technology, Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084, China
Abstract：The boundary element method (BEM) was used to analyze a cathodic protection (CP) system consisting of large pipeline structures. A three-dimensional pipe boundary element model was used to reduce the number of elements on the pipelines as well as the element integral computations. The pipelines were meshed with line elements with the boundary integrals were based on the original shapes. The large-scale CP problem was solved on a common desktop computer using the fast multipole method (FMM) to accelerate the BEM. The nonlinearity introduced by the polarization curve at the cathode was solved iteratively. The numerical results demonstrate that the number of elements can be reduced by one order of magnitude when discretizing pipelines with these line elements compared with triangular elements and that the FMM can solve large CP problems with up to 50 000 dimension of freedoms (DOFs).
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LIU Liqi, WANG Haitao. Fast boundary element method based on a 3D pipe model for analyzing cathodic protection. Journal of Tsinghua University(Science and Technology), 2015, 55(9): 1003-1009.
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