吉林大学学报(地球科学版) ›› 2016, Vol. 46 ›› Issue (5): 1538-1549.doi: 10.13278/j.cnki.jjuese.201605302
严家斌, 皇祥宇
Yan Jiabin, Huang Xiangyu
摘要:
采用广义变分原理,基于矢量基函数详细推导了大地电磁三维矢量有限元方程。为了提高计算精度和效率,应用直接法强加边界条件改善总体系数矩阵的条件数,同时使用SSOR(symmetric successive over relaxation)预处理的双共轭稳定梯度法求解复对称大型稀疏线性方程组。并利用国际标准模型与相关参考文献的结果进行了对比,验证了算法的准确性。对一个典型的三维低阻体模型进行正演,得到了不同测线的视电阻率和相位断面图,并与二维正演结果进行对比分析。结果表明:在x方向测线上,ρyx变化幅度较ρxy小,中心测线上的ρyx和ρxy响应均与二维TM模式条件下的响应特征相似。
中图分类号:
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