结构噪声核心价值与理论逻辑解读第二部分:阻振质量与复杂巨系统

Core value and theoretical logic of structure-borne noise. Part 2: blocking mass and complex huge systems

[目的]与单层、双层和浮筏隔振相比,阻振质量对结构纵波和弯曲波传导衰减很小,研究人员少有兴趣应用这类措施。然而当潜艇声隐身进入"深水区",设计人员有必要用新思维重新审视阻振质量。[方法]为此,应用波传播法(WPA)深入分析简单系统阻振质量的衰减特性,建立其在复杂巨系统中的"统计概念"并指导工程实践。[结结果]结果表明:在集成概念中,阻振质量在巨系统中因累积衰减不再是小量;在无法应用阻抗较低的"软措施"的控制场合,将声隐身设计融入结构功能设计,采用阻抗较高的"硬措施"是发展的必由之路;应建立"间断点"概念和统计理念来研究结构噪声。[结论]从"软措施"到"硬措施"的逐渐转化与演进,对声隐身跨越具有核心价值,也是创新灵感的来源!

[Objectives]Compared with 1-stage,2-stage and raft vibration isolation,the attenuation of longitudinal wave and bending wave transfer for blocking mass is low,and relatively few scholars are interested in studying the application of these measures.However,with the development of submarine noise and vibration reduction,designers should survey such less effective measures as blocking mass.[Methods]In this paper,the attenuation characteristics of blocking mass in a simple system are analyzed via the Wave Propagation Approach(WPA).Combined with engineering practices,a"statistical concept"of blocking mass in complex huge systems is proposed.[Results]The results show that the accumulative attenuation of the structure-borne noise of blocking mass in such huge systems as submarines is no longer low,though the attenuation is low for a single blocking mass.As such low-impedance"soft measures"as vibration isolation are not applicable in many cases,the only way to improve the acoustic signature of a submarine is to apply high-impedance"hard measures"in acoustic design,forming a hypostatic union with structural and functional design.In addition,structure-borne noise with the"discontinuity point"concept and statistical ideas should be important subjects for future study.[Conclusions]The gradual transformation and evolution from"soft measures"to"hard measures"form the core value of the leaping acoustic signature of submarines,and this is the source of innovative inspiration.