基于非结构化网格的2.5-D直流电阻率自适应有限元数值模拟

Abstract

In 2.5-D DC resistivity modeling with the finite-element method, models are often subdivided and refined according to user′s experiences.Moreover, the regular elements like rectangle are usually adopted.Due to these, it will need more efforts to simulate complicated models.To deal with these problems, we present an adaptive finite-element technique for 2.5-D DC resistivity modeling.A robust posteriori error estimator is incorporated to automatically predicate the new element size for the next mesh until the specified target condition is satisfied.Moreover, unstructured triangulation is employed for the discretizaiton of arbitrary complex models.Base on these, we use a vertical contact model to discuss the efficiencies of different adaptive schemes.The comparison shows that, the elements near the source points are highly refined to eliminate the singularity during the adaptive process.Furthermore, the numerical results for different schemes all can converge to the analytical solution in the final generated mesh.Finally, two additional models: a 2-D inhomogeneity buried in the homogenous half space and a 2-D valley model are tested to show the distinctive performance of our adaptive finite-element algorithm.