A finite-volume solution to the geophysical electromagnetic forward problem using unstructured grids
A finite-volume solution to the geophysical electromagnetic forward problem using unstructured grids
复制标题
DOI：
10.1190/geo2013-0312.1
复制
发表时间：
2014-10
期刊：
影响因子：
3.3
通讯作者：
H. Jahandari;C. Farquharson
中科院分区：
文献类型：
--
作者：
H. Jahandari;C. Farquharson
非结构网格的应用可以改善总场电磁问题的解，因为这些网格允许在高场梯度的位置对网格进行有效的局部加密。非结构化网格还提供了表示任意地形和地下界面所需的灵活性。我们用有限体积法研究了标准Yee交错格式在非结构四面体-Voronoi网格中的推广。我们在频域中对电场的亥姆霍兹方程进行了离散化，解决了总电场沿四面体单元边界的投影问题。为了计算观测点的电场和磁场，采用了一种利用四面体单元的边缘向量插值函数的插值法。为了验证所提方案的有效性，文中给出了两个算例，说明了有限元方法对总场和二次场的计算。
ABSTRACTThe application of unstructured grids can improve the solution of total field electromagnetic problems because these grids allow efficient local refinement of the mesh at the locations of high field gradients. Unstructured grids also provide the flexibility required for representing arbitrary topography and subsurface interfaces. We investigated the generalization of the standard Yee’s staggered scheme to unstructured tetrahedral-Voronoi grids using a finite-volume approach. We discretized the Helmholtz equation for the electric field in the frequency domain and solved the problem to find the projection of the total electric field along the edges of the tetrahedral elements. To compute the electric and magnetic fields at the observation points, an interpolation technique was employed, which uses the edge vector interpolation functions of the tetrahedral elements. To verify the presented scheme, two examples were evaluated, which revealed the computation of the total and secondary fields due to ele...