地震波方程人工边界的两种处理方法

Two processing methods for artificial boundary of seismic wave equation

1. 中国石油辽河油田分公司勘探开发研究院计算所,辽宁盘锦124010;2. 中国科学院数学与系统科学研究院计算数学与科学工程计算研究所,北京100080

1. Computing Center of Exploration & Development Research Institute of CNPC Liaohe Oilfield Company, Panjin 124010, China;2. Institute of Computational Mathematics and Scientific/Engineering Computing, Academy of Mathematics and System Sciences, Chinese Academy of Sciences, Beijing 100080, China

在分析以往人工边界处理优缺点的基础上, 提出了利用波动方程的频散关系式, 得到可以吸收任何方向入射波的自适应校正吸收边界条件和旋转校正吸收边界条件。同时, 采用波阵面法和能流密度法判别入射波方向, 克服了Pade近似吸收边界只对正入射波具有较好吸收性, 而对非正入射的波吸收性不好的缺点。数值试验结果表明了本方法的有效性。

In this paper, two absorbing boundary conditions, adaptive correction condition and rotation correction condition, were derived to absorb incident waves coming from any directions by using dispersion relation, based on an analysis of the advantages and disadvantages of existing boundary conditions. The determination of incident wave direction by wave front and energy flux density was also described. Numerical experiments were performed and their results were presented, which indicated the efficiency of these methods.