The application of a boundary element technique in combination with a contour integral approach to the numerical analysis of acoustic resonances in exterior configurations is investigated in this paper. Similar to the boundary element analysis of exterior acoustic radiation or scattering problems, spurious eigenfrequencies also turn up in the boundary element solution to exterior acoustic resonance problems. To filter out the spurious eigenfrequencies, the Burton–Miller-type combined formulation is employed to shift them from the real axis to the complex domain. The shifting effect brought by the combined formulation with different types of coupling parameters is investigated. Unlike in acoustic radiation and scattering analyses for which −i/k is suggested as the coupling parameter, it will be shown that the coupling parameter specified as β ⋅i/k with β > 0 (the time-dependent term herein is e−iωt) is more desirable in distinguishing the spurious eigenfrequencies in the boundary element analysis of exterior acoustic resonances.

中文翻译：

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Burton-Miller 公式在外部配置声共振 BEM 分析中的参数研究

本文研究了边界元技术与轮廓积分方法在外部结构声共振数值分析中的应用。与外部声辐射或散射问题的边界元分析类似，杂散特征频率也出现在外部声共振问题的边界元解中。为了滤除虚假的特征频率，采用 Burton-Miller 型组合公式将它们从实轴转移到复域。研究了不同类型耦合参数的组合公式带来的位移效应。与声辐射和散射分析不同 -一世/ķ建议作为耦合参数，将显示耦合参数指定为β ⋅一世/ķ和β > 0（这里的时间依赖项是e-一世ω吨) 在区分外部声共振边界元分析中的杂散本征频率时更可取。