当时,本地联合不稳定性将发生吸收边界状况和地波浪方程的数字计划允许精力自发地进入计算领域。也就是说,二个计划支持普通波浪解决方案,组速度指了进计算域。消除联合不稳定性的本地人的钥匙是避免如此的波浪答案。为块团在 2D 波导的 P-SV 波浪运动的有限元素模拟,为高顺序的稳定的实现的一条途径多播送的公式被提供。与一个一致矩形的网孔,它被证明并且验证那高周波的本地联合不稳定性能被设置等于或比 \ 大的元素尺寸的比率消除(\sqrt 2 \) 乘到 S 波浪速度的 P 波浪速度的比率。这些结果能为发另外的吸收边界条件导致的不稳定性问题是珍贵的。
Local coupling instability will occur when the numerical scheme of absorbing boundary condition and that of the field wave equation allow energies to spontaneously enter into the computational domain. That is, the two schemes support common wave solutions with group velocity pointed into the computation domain. The key to eliminate local coupling instability is to avoid such wave solutions. For lumped-mass finite element simulation of P-SV wave motion in a 2D waveguide, an approach for stable implementation of high order multi-transmitting formula is provided. With a uniform rectangular mesh, it is proven and validated that high-freqaency local coupling instability can be eliminated by setting the ratio of the element size equal to or greater than x/2 times the ratio of the P wave velocity to the S wave velocity. These results can be valuable for dealing instability problems induced by other absorbing boundary conditions.