Flow decomposition and aerodynamic sound generation
Flow decomposition and aerodynamic sound generation
复制标题
DOI：
10.1017/s0022112010004672
复制
发表时间：
2010-12
影响因子：
3.7
通讯作者：
S. Sinayoko;A. Agarwal;Zhiwei Hu
中科院分区：
文献类型：
--
作者：
S. Sinayoko;A. Agarwal;Zhiwei Hu
满足无界可压缩Navier-Stokes方程的流体流动变量近似分解为声辐射和非辐射分量，导致定义明确的源项，可以被识别为气动噪声的物理源。我们表明，通过过滤流场的线性卷积滤波器，它是可能的，以分解成非辐射和辐射组件的流量。这是证明了两个不同的流量：一个满足线性化的欧拉方程和其他的Navier-Stokes方程。在后一种情况下，计算对应的声源。他们被发现是更多的物理比通过经典的声学类比，其中流场被分解成一个稳定的平均值和波动的组件计算。
An approximate decomposition of fluid-flow variables satisfying unbounded compressible Navier–Stokes equations into acoustically radiating and non-radiating components leads to well-defined source terms that can be identified as the physical sources of aerodynamic noise. We show that, by filtering the flow field by means of a linear convolution filter, it is possible to decompose the flow into non-radiating and radiating components. This is demonstrated on two different flows: one satisfying the linearised Euler equations and the other the Navier–Stokes equations. In the latter case, the corresponding sound sources are computed. They are found to be more physical than those computed through classical acoustic analogies in which the flow field is decomposed into a steady mean and fluctuating component.