This paper is concerned with the application of the modal expansion method (MEM) to the vibro-acoustic simulation of flexible vibrating structures. The structural vibration field due to the external excitation is expanded by a FEM-based modal expansion method, and the corresponding normal velocity is transferred into the acoustic FE mesh that is generated for the acoustic analysis. In this kind of acoustic simulation, the numerical results are definitely influenced by the accuracy of the expanded vibration field using the modal expansion method, which is in turn influenced by the sensor placement for extracting and determining the reduced numerical mode shapes and the modal participation factors that are essential for the modal expansion method. In this context, the investigation of its effect on the numerical accuracy of the acoustic analysis is of importance. We in this paper compare the acoustic analysis results, such as the sound patterns, power, and pressures, between the regular and optimum sensor placements with MSC/Nastran results for three different boundary conditions.

本文关注的是模态扩展方法 (MEM) 在柔性振动结构的振动声学仿真中的应用。由外部激励引起的结构振动场通过基于 FEM 的模态扩展方法进行扩展，并将相应的法向速度传递到为声学分析生成的声学 FE 网格中。在这种声学模拟中，数值结果肯定会受到使用模态扩展方法扩展的振动场精度的影响，而这又受到用于提取和确定减少的数值模态振型和模态参与因子的传感器放置的影响这对于模态扩展方法是必不可少的。在这种情况下，研究其对声学分析数值精度的影响非常重要。在本文中，我们将声学分析结果（例如声音模式、功率和压力）与 MSC/Nastran 三种不同边界条件下常规和最佳传感器放置之间的结果进行了比较。