【作者】 肖邵予；

【导师】 骆东平；

【作者基本信息】 华中科技大学 ， 船舶与海洋结构物设计、制造， 2004， 硕士

【摘要】 本文对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进行了深入的研究,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。本研究基于扩展的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,以及内部声场的声压对系统结构的影响。文中以壳体和端部圆板的均方速度级和壳体内、外表面的辐射声压级作为评价结构振动声辐射水平的主要参数。理论研究计算了环肋圆柱壳和端板圆板所围空腔的平均声压级,比较了壳体和端部圆板的均方速度级,分别讨论了内部声场对壳体内、外表面的辐射声压级周向分布的影响,以及内部声场对壳体的均方速度级的影响。文章设计了环肋圆柱壳的钢制模型,进行了模型的振动实验研究,测量了其固有频率和模态,并与有限元软件ANSYS的计算结果进行了比较。更多还原

【Abstract】 The vibroacoustic characteristic about a finite stiffened-cylindrical shell closed at one end by a circular plate 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. Theoretical results are presented in radiated sound pressure, radial quadratic velocity. In this paper, the author first compared the vibroacoustic characteristic in the plate-ended circular cylindrical shell, then the effects of the sound field inside the cavity are discussed. Finally, the research of experiments on a finite stiffened cylindrical shell are also discussed in detail .The results of the experiment are compared with those of the computed by ANSYS.更多还原