水面舰船复合双层底结构隔振特性分析

摘要

为了提高水面舰船的声隐身性能，对典型的双层底结构进行了剖析和研究。由于“┻┳”形连接结构在大部分频率处的透射效率较小，同时偏心阻振质量块对振动波有较好的阻隔效果。因而，在双层底的纵桁和肋板上构造“┻┳”形连接结构和添加不同偏心距和重量的阻振质量块，形成复合的双层底结构。采用FEM法对改进前后的双层底结构的振动特性进行数值仿真计算。结果表明：在双层底内部构造“┻┳”形连接结构使结构发生突变，从而导致结构阻抗也随之发生变化，产生阻抗失配，这样在部分频段就能有效的阻断振动波的传递，而且阻振质量的偏心布置和增大阻振质量也都会在一定程度上提高隔振效果。使之复合双层底结构的声隐身性能有可能得以改善。%To improve the sound stealth performance of naval vessels, a typical double-layer infrastructure was studied for the vessels. The“┻┳”shaped linking structure, which has smaller wave refraction effect in a wide frequency range, was constructed in longerons and ribs of the double-layer infrastructure. The eccentric mass blocks, which have good vibra-tion isolation effects, were added to the infrastructure. The finite element method was used to simulate the vibration charac-teristics of the infrastructure. The results show that the“┻┳”shaped linking structure built in the double-layer infrastruc-ture can increase the structural impedance greatly and yield impedance mismatch, so that the transmission rate of vibration can be reduced. And the eccentric blocking mass and gaining weight can improve the effect of the vibration isolation. Thus, it is verified that the double-layer infrastructure has good sound stealth performance for naval vessels.