基于质点振速输入和Laplace变换的流动媒质中近场声全息技术  

Nearfield Acoustic Holography in a Moving Medium based on Particle Velocity Input and Laplace Transform

作　　者：董必春 张润梅 陈雪辉 DONG Bichun;ZHANG Runmei;CHEN Xuehui(School of Mechanical and Electrical Engineering, Anhui Jianzhu University, Hefei 230601, China)

机构地区：[1]安徽建筑大学机械与电气工程学院,合肥230601

出　　处：《噪声与振动控制》2018年第A02期453-456,共4页Noise and Vibration Control

基　　金：安徽省高等学校自然科学研究重点项目(KJ2015A013)

摘　　要：流动媒质中近场声全息技术(NAH)是一种能够实现流动媒质中声源识别和声场重建的先进技术。大多数流动媒质中NAH算法都是以声压作为输入量,但在测量声压时,传声器和媒质之间相互作用会产生气动背景噪声。得益于质点振速能够利用光学方法进行测量(例如LDV),以质点振速作为输入量的流动媒质中NAH具有一定的优势。然而,当以质点振速作为输入时,经典的基于空间Fourier变换的流动媒质中NAH算法存在奇异性问题,导致该方法具有不稳定性。鉴于此,本文提出了基于Laplace变换的流动媒质中NAH技术,在时间上利用Laplace变换代替Fourier变换,从理论上消除了奇异性,进而实现了基于质点振速输入时流动媒质中声场的精确重建。仿真结果表明,所提出的方法具有良好的声场重建效果。Nearfield acoustic holography（NAH） in a moving medium is an advanced technique, which can be used for the sound source identification and the sound field reconstruction in the environment of moving medium. In most NAH procedures, the sound pressure is used as the input. However, the interaction between microphones and moving medium will cause aerodynamic background noise. Since particle velocity can be measured by optical methods（e.g. LDV）, NAH in a moving medium based on particle velocity input has its advantages. However, there is the singular problem for the classical spatial Fourier transform-based NAH in a moving medium, and it will result in instability. In view of this, in this paper, NAH in a moving medium based on Laplace transform is proposed. In the proposed method, Fourier transform is replaced by Laplace transform in the time domain. Thus, the singular problem can be resolved theoretically, and the accurate sound field reconstruction in a moving medium can be realized based on particle velocity input. The results of numerical simulation show that the proposed method works well for sound field reconstruction.

关 键 词：声学 近场声全息 流动媒质 质点振速 奇异性 

分 类 号：TB532[理学—物理]