两端用圆板封口的环肋柱壳振动声辐射性能分析

研究两端用圆板封口的环肋圆柱壳结构在流场中的振动声辐射特性,着重分析了由环肋圆柱壳和端部圆板所围空腔的内部声场对整个系统结构振动和声辐射的影响.基于扩展的Rayleigh-Ritz法,利用Hamilton变分原理推导出圆柱壳与圆板的耦合振动方程.考虑了静水压力的影响,环肋圆柱壳与端部圆板之间采用二自由度弹簧模拟弹性连接的等效刚度.环肋圆柱壳声辐射的研究中,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,该表达式对有限长圆柱壳进行Fourier积分变换得到壳体外表面辐射声压的解;用Green函数法来求解环肋圆柱壳和端板所围空腔的内部压力场.

Vibroacoustic Analysis of a Finite Stiffened-Cylindrical Shell Closed by Circular Plates

The vibroacoustic characteristic about a finite stiffened-cylindrical shell closed by circular plates is analyzed in this paper.The effects of the generated sound field inside the cavity are presented. Based on the expanded Rayleigh-Ritz method, the coupled vibration equations are formulated by means of Hamilton variational principle, in which the effects of hydrostatic pressure and the full coupling between the subsystems(plate,shell and cavity) are considered,the elastic joint between the shell and the plate are simulated by springs with possible permitted freedom. The sound radiation field out of the shell is resolved by applying Helmholtz equation and the continuity conditions of the displacement on the surface of fluid-structure, and the expression of sound pressure is obtained by Fourier transform; the sound radiation field inside the cavity is obtained through Green's function method.