两封闭弹性柱状体连接结构的辐射声场分析

Analysis of Sound Radiation of Two Elastic Cylindrical Enclosures Connected by Mechanical Joints

利用汉密尔顿函数和瑞利-李兹方法,建立了不同边界条件下两封闭弹性圆柱腔体连接结构的外辐射声场模型。通过在两弹性柱状结构的端板连接点处施加假想的弹簧模拟了不同的连接条件,推导出了连接结构外辐射声场的解析解。该模型充分考虑了柱状体内部结构之间的振动耦合、弹性柱状体结构与腔体内声场之间的耦合以及由连接点引入的两柱状结构之间的振动耦合。通过算例表明,弹性结构的辐射声场主要由其中的直接受力结构的辐射声场所决定;两弹性柱状结构连接点处旋转弹簧的刚度变化对整个结构辐射声场的影响较线弹簧小。研究结果为工程中连接结构辐射噪声的分析和控制提供了一定的理论依据。

A model of sound radiated from two connected cylindrical enclosures with a wide variety of boundary conditions was deduced by using Hamiltonian function and Rayleigh-Ritz method herein.By means of artifical springs along the connected points of two flexible panels,this model allowed the consideration of structural joint conditions.A general formulation considering the full coupling between the subsystems（plates,shell and cavities） was developed.Two main issues were reached.One is that the sound radiation of the enclosure structure is governed by the substructure excited directly,the other is that the rotational stiffness of connected points has less influence on the sound radiation than the translational stiffness has.The contribution and highlight of this paper are that it provides some supports in engineering theoretically.