Finite element numerical simulation of 2.5D direct current method based on mesh refinement and recoarsement
Zhang Qian-Jiang1,2, Dai Shi-Kun1, Chen Long-Wei2, Qiang Jian-Ke1, Li Kun1, and Zhao Dong-Dong1
1. School of Geosciences and info-physics, Central South University, Changsha 410083, China.
2. College of Earth Sciences, Guilin University of Technology, Guilin 541006, China.
Abstract To deal with the problem of low computational precision at the nodes near the source and satisfy the requirements for computational efficiency in inversion imaging and finite-element numerical simulations of the direct current method, we propose a new mesh refinement and recoarsement method for a two-dimensional point source. We introduce the mesh refinement and mesh recoarsement into the traditional structured mesh subdivision. By refining the horizontal grids, the singularity owing to the point source is minimized and the topography is simulated. By recoarsening the horizontal grids, the number of grid cells is reduced significantly and computational efficiency is improved. Model tests show that the proposed method solves the singularity problem and reduces the number of grid cells by 80% compared to the uniform grid refinement.
This work was financially supported by the National Natural Science Foundation of China (No. 41574127 and 41174104) and the National Key Technology R&D Program for the 13th five-year plan (No. 2016ZX05018006-006).
Cite this article:
. Finite element numerical simulation of 2.5D direct current method based on mesh refinement and recoarsement[J]. APPLIED GEOPHYSICS, 2016, 13(2): 257-266.
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2016, Vol. 13 
