两端剪力薄膜支撑圆柱壳体的点导纳特性

Point mobilities of circular cylindrical shells with both ends supported by shear diaphragms

针对两端剪力薄膜支撑各向同性圆柱壳体的动力响应问题,基于多种经典薄壳理论及模态叠加原理,考虑到非径向振动惯性项的贡献,同时计入正余弦模态的响应,推导了圆柱壳体同时受简谐集中力与力矩激励下的力导纳、力矩导纳以及耦合导纳的完整解析表达式。算例表明,圆柱壳体运动方程中的非径向振动惯性项对各阶模态及导纳幅频的预估精度影响显著;耦合导纳实部具有可负性规律,对输入壳体的振动能量起着重要作用。旨在为两端剪力薄膜支撑圆柱壳体结构的减振降噪和以其为支承基础的主被动隔振系统的设计提供理论指导。

Classical thin shell theories and modal superposition principle were used to investigate the dynamic response of isotropic circular cylindrical shells with both ends supported by shear diaphragms. The contribution of nonradial vibration terms and responses of their sinusoidal and cosine modes were taken into account. The force mobility,moment mobility and coupling mobility functions of a circular cylindrical shell simultaneously subjected to harmonic point force and moment excitations were derived. It was shown that non-radial vibration terms have remarkable effects on the prediction accuracy of amplitude frequencies of modes and mobilities,and the real parts of coupling mobility functions may be negative. The results provided a theoretical guidance for the vibration and noise reduction of cylindrical shell structures with both ends supported by shear diaphragms and for designing active and passive vibration isolation systems with these circular cylindrical shells as foundations.