The scaled boundary finite element method (SBFEM) has obvious advantages in simulating both finite and infinite domains. However, the present high-order transmission boundary of SBFEM has a problem in numerical stability, especially for 3D fluid–structure interaction (FSI) problems. In this paper, a modified method is put forward to improve the numerical stability of the high-order transmission boundary and the total field formulas of the modified high-order transmission boundary are derived. In the transient response analysis, the nonreflecting characteristics of the infinite fluid domain are simulated by the modified high-order transmission boundary, while the impacts loading is calculated by the total field formulas. Several numerical examples are presented to prove the validity of the modified high-order transmission boundary and the total field formulas.

中文翻译：

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基于全场公式和修正高阶传输边界的水下结构瞬态响应分析

缩放边界有限元法（SBFEM）在模拟有限域和无限域方面都具有明显的优势。然而，目前 SBFEM 的高阶传输边界在数值稳定性方面存在问题，尤其是对于 3D 流固耦合（FSI）问题。本文提出了一种改进高阶传输边界数值稳定性的改进方法，并推导了改进后的高阶传输边界的总场公式。在瞬态响应分析中，无限流体域的非反射特性通过修正的高阶传输边界进行模拟，冲击载荷通过总场公式计算。