多设备源激励下水中柱壳结构声振特性研究

Vibro-acoustic Characteristics of Submerged Cylindrical Shells under Multiple Excitations

研究多个设备振动激励下的水中有限长圆柱壳体振动与声辐射特性。基于薄壳理论,建立单频多个设备振动激励下水中有限长圆柱壳体的声振耦合方程,采用模态展开法推导出多源激励下壳体振动响应和辐射声功率的解析表达式,分析设备激励源数、激励形式及其组合方式等对壳体振动响应和辐射声功率的影响规律。研究表明:多设备振动激励作用下,施加的多点激励力间距越大,壳体结构振速响应和辐射声功率越低;沿周向施加线激励力,不易激起壳体振动与声辐射,而沿轴向施加的激励力越集中,所激起壳体的振动与声辐射越强;在激励力合力相同的条件下,增加激励力接触面积可有效隔声。研究结果可为水下航行体的振动噪声控制提供理论依据。

Vibration and sound radiation characteristics of submerged finite cylindrical shells under multiple excitations are researched. Based on thin shell theory, the vibro-acoustic coupling equations of the shell under multiple excitations are established. Then, the analytical solutions of the vibration response and the sound radiation power of the shell are formulated in terms of modal expansion method. Influences of the multiple excitations on the vibration response and acoustic radiation of the shell are analyzed. The results show that the vibration response and radiation power decrease with the increase of the spacing of the excitations. Circumferential excitations can hardly trigger the vibration and acoustic radiation of the shell. Concentration of the axial excitation forces can induce strong vibration response and acoustic radiation. Enlarging the contact area of the excitation force can lead to good sound insulation effects. Results of the research can provide a theoretical basis for vibration and noise control of underwater vehicles.