基于板壳耦合结构的浮筏主动隔振及结构声辐射主动控制研究

A general analytical model of an active floating raft isolation system based on a strongly coupled plate-cylindrical shell structure under arbitrary boundary and coupling conditions is proposed in this research. A multi-dimentional improved Fourier series method is employed to model the cylindrical shell under arbitrary elastically boundary conditions and the coupling connection between the plate and the shell. So the coupled dynamic model of an active floating raft-elastic plate/cylindrical shell structure with arbitrary boundary and coupling conditions is developed by impedance and mobility analysis. Then the mathematical relationship between vibration transmission of the floating raft and sound radiation of the shell can be obtained by expanding the sound radiation of the shell through sound radiation mode theory. In particular, we seek to deepen the understanding of the relationships between the excitations, transmission paths, and the radiation efficiencies of the coupled system, and hence to develop an effective active vibration isolation strategy and realizations. This research also sets out to explore, by taking advantage of the phase lags between the multiple excitation sources, to regulate the energy flows and sound radiation from the structure. We believe this study will lead to significant progresses in understanding the inherently control mechanism of sound radiation by active floating raft isolation arrangement, and untimately advancing the applications of active control technologies in marine science and systems. It can also be expected that this work will have profound impacts on both academic research and practcal applications in relating to active floating raft techniques for noise and vibration control of marine power machines.

本项目采用解析方法建立任意边界和强耦合条件下弹性板-圆柱壳耦合结构为基础的浮筏主动隔振系统的统一数学描述。其思路是采用多维改进傅里叶级数方法解决边界任意约束下圆柱壳的动力学建模及板壳耦合边界的处理，通过阻抗导纳法得到浮筏主动隔振系统-任意边界和耦合条件下弹性板-圆柱壳耦合结构的系统动力学模型。在此基础上，通过将弹性板-圆柱壳耦合结构对外声辐射用辐射声模态展开，得到浮筏隔振系统振动传递与圆柱壳结构对外声辐射的数学物理关系，深入探讨振源特性、耦合系统振动特性、传递途径与对外结构声辐射之间的内在关系，从而提出有效的基于圆柱壳对外声辐射控制的浮筏主动隔振策略。本项目还将进一步探讨浮筏隔振系统多个振源之间的相对相位对功率流传递、声辐射控制的影响。通过本项目的深入研究，有助于加深对浮筏主动隔振对结构声辐射控制机理的理解，探索和推动浮筏主动隔振技术在舰船领域的应用。从而具有重要的学术意义和工程应用价值。

本项目以控制声辐射为目标，研究浮筏主动隔振及同步定相控制技术，完成以下研究工作：建立了任意边界和耦合条件下、弹性板-圆柱壳耦合结构为基础的浮筏主动隔振系统及结构声辐射耦合模型的通用数学描述，在此基础上通过探讨耦合系统结构振动特性、功率流传递特性与对外声辐射之间的耦合关系，研究弹性板-圆柱壳耦合结构为基础的浮筏隔振系统对外声辐射的规律。采用二进制遗传算法探讨并形成大型舱段结构上浮筏主动隔振系统误差传感器的优化布置方法，通过理论仿真和试验验证；基于相对相位遗传优化算法的浮筏同步定相控制技术也得到了仿真和试验结果的验证。项目研究成果对船舶大型浮筏结构的振动控制和水下声辐射控制有重要的参考意义和工程应用价值。本项目共资助项目组成员参加4次国际会议共18人次，其中包括主题报告1次，邀请报告2次，项目组成员担任分会主席4次，大会主席1次；在国内做学术报告8次。本项目邀请境外学者来华访问8人次。培养博士研究生8人，硕士研究生4人。标注本项目已发表的学术文章28篇（含期刊论文16篇，会议论文12篇，其中SCI收录8篇，EI收录20篇）；已录用未发表的学术论文1篇，为SCI源期刊论文。