频率域线源大地电磁法有限元正演模拟

本文介绍了频率域线源大地电磁法有限元正演模拟的研究结果. 在外边界上统一应用适合于人工源的一阶吸收边界条件来形成边值问题，可减小基于平面波假设造成的人为截断边界的影响. 程序编辑中设计了两个二维数组分别存储总体系数矩阵的非零元素和在总体结点编号中的位置，使内存占用量减少，且物理意义明确，方便用高斯-赛德尔等迭代法解有限元方程时调用. 采用视δ函数模拟线源，提高了解方程组的稳定性. 最后通过对1个简单模型和1个复杂模型的模拟,证明所用的方法对异常体能够有明显的反映，说明了该方法的可靠性和有效性.

Electromagnetic modeling due to line source in frequency domain using finite element method

The research result of electromagnetic modeling with line source in frequency domain using the finite element method is presented. The first order absorption boundary condition is applied to the outside boundary, which can avoid the error caused by the plane wave assumption. We design two arrays to store the total coefficient matrix with non_zero elements and the corresponding node matrix, respectively, which reduce the consumption of memory. At the same time, the physical meaning is simple and easy to be understood, and it is convenient to find solutions of FEM equations by using the Gauss_Seidel iteration method. The pseudo δ function is used to enhance the stability of solving the equations set. Finally a simple and a complex model are used to test the reliability and effectivity of the method.