湍流边界层压力起伏激励下弹性板的噪声辐射  

Noise radiation of an elastic plate excited by turbulent boundary layer pressure fluctuations

作　　者：汤渭霖 

机构地区：[1]哈尔滨船舶工程学院,哈尔滨150001

出　　处：《声学学报》1991年第5期352-364,共13页Acta Acustica

摘　　要：本文提出一个统一的理论计算湍流边界层压力起伏激励下无限大弹性板的噪声辐射。用波数-频率谱传递函数表征包括弹性板和流体负荷在内的整个系统的特性,导出了噪声场互谱函数的一般表示式。这是复波数平面上的一个积分,它可以归结为两类极点的留数和。由于压力起伏的迁移峰引入的极点产生直接传递的噪声场,它在流体中呈现为渐消的非均匀波,因为这个极点处在高波数区。另一些由于结构传递函数引起的极点产生带有流体负荷的板的共振辐射场。这些极点的位置和留数可以用共振散射理论进行近似计算。对于水动力噪声情况,感兴趣的频率厚度乘积相当低,这时零阶对称模式对噪声辐射起主要作用。A unified theory for calculating the noise radiation of an infinite elastic plate excited by turbulent boundary layer pressure fluctuations is presented. Using the wavenumber frequency transfer function to describe the whole system consisting of the plate and the liquid loading, a general expression of the cross spectrum was derived. It is an integral in the complex wavenum-ber plane and leads to a sum of the residues at the poles of two types. One pole introduced by the convectivc ridge of pressure fluctuations yield a direct transfer component, which is an evanescent wave in liquid because the pole lies in the high wavcnumber region. The poles introduced by the transfer function of the structure produce the radiation field components with the resonance modes of a liquid loaded plate. The pole positions and their residues can be computed approximately by use of the Resonance Scattering Theory. For the case of hydrodynamic noise, in which the range of the frequency-thickness product of interest is relatively low, the symmetric zero-order mode dominates the noise radiation.

关 键 词：湍流 边界层 弹性板 噪声 辐射 

分 类 号：TB53[理学—物理]