Gao Yingjie, Zhang Jinhai, Yao Zhenxing
Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, China
J Acoust Soc Am. 2015 Dec;138(6):EL551-7. doi: 10.1121/1.4938270.
The complex frequency shifted perfectly matched layer (CFS-PML) can improve the absorbing performance of PML for nearly grazing incident waves. However, traditional PML and CFS-PML are based on first-order wave equations; thus, they are not suitable for second-order wave equation. In this paper, an implementation of CFS-PML for second-order wave equation is presented using auxiliary differential equations. This method is free of both convolution calculations and third-order temporal derivatives. As an unsplit CFS-PML, it can reduce the nearly grazing incidence. Numerical experiments show that it has better absorption than typical PML implementations based on second-order wave equation.
复频移完全匹配层（CFS-PML）可以提高完全匹配层对近掠入射波的吸收性能。然而，传统的完全匹配层和复频移完全匹配层是基于一阶波动方程的；因此，它们不适用于二阶波动方程。本文提出了一种使用辅助微分方程实现二阶波动方程复频移完全匹配层的方法。该方法既不需要卷积计算，也不需要三阶时间导数。作为一种非分裂的复频移完全匹配层，它可以减少近掠入射。数值实验表明，它比基于二阶波动方程的典型完全匹配层实现具有更好的吸收效果。
