摘 要：本文研究了安装浮筏系统的有限圆柱壳体的振动和声辐射特性，建立由机器-浮筏-艇体组成的一个复杂动力系统的有限元/边界元模型，并采用该模型对三种方案，即一个舱段、三个舱段、全艇进行水下噪声级预报；讨论了三种不同方案对壳体表面振速和水下辐射噪声级的影响规律，结果表明在潜艇舱段首阶弯曲振动的共振频率以下，用一个舱段模拟整艇的动态特性是不合适的；在高于此频率，采用舱段模型来预报整艇的表面振速是可以接受的。

ABSTRACT: Vibration and acoustic radiation characteristics of a finite cylindrical shell with a floating raft are investigated in this paper. A FEM/BEM model is established for the complex dynamic system composed of machineries, floating raft, and the shell, with which three projects, i.e., one cabin, three cabins, and whole submarine, are considered for the prediction of the underwater sound level. Discussions are presented for the influences of three different projects on the shell’s surface vibration velocity and the far-field acoustic radiation, which indicate that below the resonance frequency for the first bending mode of the submarine cabin, it’s improper to simulate the dynamic characteristics of a whole submarine with one cabin model, and above this frequency, it’s acceptable for using a cabin model to predict the shell surface velocity of a whole submarine.