近场声全息的算法和实验研究

发布时间：2019-03-09 08:21

【摘要】：近场声全息(NAH)技术是一种非常有效的噪声源识别、定位和声场可视化技术,它根据声源附近全息面上测量的复声压量可以重建出整个三维辐射声场中任意点处的声压、质点速度矢量、声强矢量以及声源的辐射声功率等声学量。在过去的二十多年中,该技术取得了很大的发展,形成的全息变换算法主要有：空间声场变换(STSF)、边界元方法(BEM)和Helmholtz方程最小二乘法(HELS)。本文对几种全息变换算法进行了介绍,实现和改进了基于STSF方法的NAH技术。在此基础上,设计了一款应用于NAH实验的传声器阵列架,并通过金属薄板激振实验对STSF算法进行了验证。然后,将基于STSF的NAH基本算法应用于故障模拟试验台的噪声源识别中,通过实验展示了近场声全息在噪声源识别中的效果,并指出了在应用中存在的问题。本文主要做了以下几个方面的研究： (1)回顾近场声全息技术的发展历史,分析了研究现状和存在的问题,在此基础上提出了这些问题的解决途径。 (2)实现基于STSF的近场声全息技术,解决该技术中的若干关键问题。采用特殊函数和分离变量法推导出平面NAH的理论公式,分析误差并讨论算法的数值实现。 (3)针对近场声全息测量,分析其测量流程、测量仪器和测量装置,在此基础上,设计了一款应用于NAH实验的传声器阵列架,并通过金属薄板激振实验对STSF算法进行了验证。 (4)将基于STSF的NAH基本算法应用于故障模拟试验台的噪声源识别中,通过实验展示了近场声全息在噪声源识别中的效果,并指出了在应用中存在的问题。 (5)对全文的研究工作进行总结,并指出了有待进一步研究的课题。
[Abstract]:Near-field acoustic holography (NAH) is a very effective technique for noise source identification, localization and visualization of sound field. It can reconstruct the sound pressure at any point in the whole three-dimensional radiation sound field according to the complex sound pressure measured on the holography near the sound source. Particle velocity vector, sound intensity vector and sound source radiation sound power and other acoustic quantities. In the past two decades, this technique has made great progress. The main algorithms of holographic transformation are as follows: spatial acoustic field transformation (STSF), boundary element method (BEM) and Helmholtz equation least square method (HELS). In this paper, several holographic transformation algorithms are introduced, and the NAH technology based on STSF method is implemented and improved. On the basis of this, a microphone array frame applied to NAH experiment is designed, and the STSF algorithm is verified by the vibration experiment of metal sheet. Then, the basic NAH algorithm based on STSF is applied to the noise source identification of fault simulation test-bed. The effect of near-field acoustic holography in noise source identification is demonstrated by experiments, and the problems existing in the application are pointed out. The main contents of this paper are as follows: (1) the development history of near-field acoustic holography is reviewed, the present research situation and existing problems are analyzed, and the solutions to these problems are put forward. (2) the near-field acoustic holography based on STSF is realized, and some key problems in this technique are solved. The theoretical formula of plane NAH is derived by means of special function and separated variable method. The error is analyzed and the numerical realization of the algorithm is discussed. (3) for near-field acoustic holography, the measuring flow, measuring instrument and measuring device are analyzed. On the basis of this, a microphone array frame applied to NAH experiment is designed, and the STSF algorithm is verified by metal sheet excitation experiment. (4) the basic algorithm of NAH based on STSF is applied to the noise source identification of fault simulation test-bed. The effect of near-field acoustic holography in noise source identification is demonstrated by experiments, and the problems existing in the application are pointed out. (5) summarize the research work of the full text and point out the topics to be further studied.
【学位授予单位】：昆明理工大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TB52

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