【摘要】 通过对具有内部浮动甲板(浮筏)的环肋圆柱壳结构在流体中的振动、声辐射特性的研究,就能够比较真实的揭示潜艇动力舱的振动和声辐射特点.本文采用四自由度弹簧技术来模拟圆柱壳体和浮动甲板之间的弹性连接,基于扩展的Rayleigh Ritz法,运用Hamilton变分原理导出壳体与甲板的耦合振动方程,并利用Helmholtz波动方程和流固交界面上的速度相容条件求得壳体表面辐射声压的表达式.进而讨论了在弹簧连接刚度一定时,浮动甲板刚度的变化以及其垂向位置的变化对圆柱壳的振动、声辐射特性的影响.结果表明,甲板刚度变化对壳体的振动和声辐射的影响比较复杂,与激励频率有关;甲板圆心角的增加会增大壳体的辐射声功率级.更多还原

【Abstract】 Compared to a cylindrical shell, the stiffened cylindrical shell with internal longitudinal floating deck is a more realistic model for the power cabin of underwater vehicles. The vibro-acoustic characteristic about the deck-partitioned cylindrical shell is generally concerned. Based on the expanded Rayleigh-Ritz method, the coupled vibration equations were formulated by means of Hamilton variational principle, in which the elastic joint between the shell and the deck were simulated by springs with possible permitted freedom. The sound radiation field out of the shell was resolved by applying the Helmholtz equation and the continuity conditions of the displacement on the surface of fluid-structure, and the expression of sound pressure was obtained by Fourier transform. The effects of the stiffness and location of the floating deck were also dicussed. The results show that the effects of the floating deck rigidity on vibration and sound radiation of the shell are complicated and related to the driving frequency. Moreover, the bigger the central angle of floating deck is, the higher the sound radiation power is.更多还原