Recent Trends in Wave Mechanics and Vibrations - Proceedings of WMVC 2022
Recent Trends in Wave Mechanics and Vibrations - Proceedings of WMVC 2022
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波动力学和振动的最新趋势 - WMVC 2022 论文集
DOI：
10.1007/978-3-031-15758-5_112
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发表时间：
2023
期刊：
影响因子：
--
通讯作者：
Casado P
中科院分区：
文献类型：
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作者：
Casado P
声学相机是一种成熟且高效的设备，通过使用来自压力传感器阵列（麦克风）的多个同时采集的信号来定位声源。声学相机本质上提供了一种高度定向的传感器，其中来自阵列的操纵主波束中的噪声源的信号相对于背景噪声被高度放大，背景噪声从主波束以外的所有方向到达相机，因此被抑制。声相机的基本原理是波束形成数据处理方法，波束形成数据处理方法广泛应用于传感器阵列配置，并起到空间滤波操作的作用。该团队的长期愿景是开发一种类似的设备，称为地震照相机，它可以定位由水泄漏产生的噪声源的方向。这是一个3轴检波器阵列，分布在疑似泄漏点附近的地面上，用于定位和量化水泄漏，其准确性和可靠性明显高于仅在泄漏点两侧使用两个传感器的传统方法。地震相机不同于声波相机，因为数据阵列是矢量的（三轴检波器提供速度而不是标量压力场），两种或两种以上的波类型（纵波、横波和面波）同时传播，土壤性质随着位置、类型和条件的不同而变化很大。在初步的可行性研究中，考虑了由解析弹性方程计算的时域解来生成数值数据。波场由直接从泄漏处辐射的球形纵波组成，这里将泄漏模拟为半径的球形腔。为了研究用于检测泄漏的延迟和波束形成算法的实现，详细阐述了所获得的数值数据。最后，讨论了自由表面和传感器测量方向对波束形成的影响，结果表明，该波束形成算法在无限介质模型中效果更好，精度更高，尽管半空间模型仍然具有令人满意的结果。
The acoustic camera is an established and highly effective device for localising acoustic sources by the use of a number of simultaneously acquired signals from an array of pressure sensors (microphones). The acoustic camera essentially provides for a highly directional sensor in which the signals arriving from the noise source in the steered main beam of the array are highly amplified relative to the background noise, which arrives at the camera from all directions outside the main beam and is therefore suppressed. The underlying principle of the acoustic camera is the beamforming data processing method which is widely applied in sensor array configurations and acts as a spatial filtering operation. The long term vision of the team is to develop an analogous device, termed here seismic camera, which allow to locate the direction of the noise sources generated from water leaks. This is an array of 3-axis geophones distributed on the ground in the vicinity of the suspected leak to localise and quantify water leaks with significantly greater accuracy and reliability than conventional methods that use just two sensors either side of the leak. The seismic camera differs from the acoustic camera since the array of data is vectorial (three axis geophones provide velocities instead of a scalar pressure field), two or more wave types (compressional, shear and surface waves) propagate simultaneously and the soil properties varies greatly with location, type and condition. In this preliminary feasibility study a time-domain solution calculated from the analytical elasticity equations is considered to generate the numerical data. The wave field is composed by spherical compressional waves radiating directly from the leak which is modelled here as a spherical cavity of radiusa. The obtained numerical data is elaborated in order to look at the implementation of the Delay-and-Sum beamforming algorithm for the detection of the leak. Finally, the effects of wave reflection caused by a free surface and the sensor direction of measurement are discussed and it is shown that the beamforming algorithm works better and more precisely in infinity medium models, although the half-space model still presents satisfactory result.