论文标题
随机流中的相干干涉成像
Coherent interferometric imaging in a random flow
论文作者
论文摘要
本文涉及成像方法的开发，该方法将源或反射源定位在不均匀的移动介质中，并以声波传播了它们。一个典型的例子是宽带声源在湍流射流流中的定位，用于航空声音应用。所提出的算法是Kirchhoff迁移（KM）和相干干涉法（CINT）的扩展，这些算法已考虑到迄今为止平滑且随机的不均匀静态介质。它们是从线性化的Euler方程开始的，用于固定环境流的声学扰动。解决了固定点源在具有恒定速度的环境流中产生的声波传播的模型问题。基于此结果，提出了成像功能来修改现有的KM和CINT功能以说明环境流速度。随后，通过各种配置中的数值模拟对它们进行了测试和比较，包括合成的湍流喷气机代表实际射流流中遇到的主要特征。
This paper is concerned with the development of imaging methods to localize sources or reflectors in inhomogeneous moving media with acoustic waves that have travelled through them. A typical example is the localization of broadband acoustic sources in a turbulent jet flow for aeroacoustic applications. The proposed algorithms are extensions of Kirchhoff migration (KM) and coherent interferometry (CINT) which have been considered for smooth and randomly inhomogeneous quiescent media so far. They are constructed starting from the linearized Euler equations for the acoustic perturbations about a stationary ambient flow. A model problem for the propagation of acoustic waves generated by a fixed point source in an ambient flow with constant velocity is addressed. Based on this result imaging functions are proposed to modify the existing KM and CINT functions to account for the ambient flow velocity. They are subsequently tested and compared by numerical simulations in various configurations, including a synthetic turbulent jet representative of the main features encountered in actual jet flows.
