多次透射边界是一种应用广泛的人工边界模拟方法,但类似于其它人工边界,它也存在计算稳定性问题。利用在透射边界区附加黏弹性元件的方案,探讨了在波动数值模拟中消除多次透射边界计算失稳的措施,该措施中弹簧和阻尼元件被附加在透射边界区内的;占限元网格点上。数值计算分析表明,该措施是一种处理透射边界计算飘移失稳的有效措施,对透射边界的零频飘移:失稳有较好的抑制作用,但该措施对抑制透射边界的高频失稳没有明显效果。
The multi-transmitting boundary is a local artificial boundary widely used in numerical simulation of the near-field wave motion in infinite media. But like other artificial boundaries, the multi-transmitting boundary has the instability of numerical simulation. The measure is steadied for eliminating the instability of the transmitting boundary by means of adding visco-elastic elements in the artificial boundary area. In the measure, the spring-damper elements are emplaced at the finite element nodes next to the artificial boundary in the artificial boundary area. Validity of the suggested measure is tested by numerical analysis. The results show that the proposed measure is effective to solve the drift instability of multi-transmitting boundary, which is valid for eliminating the drift instability but no visible effects on the high-frequency instability.