Lai Junpeng, Liu Zihan, Karimi Morteza, Farahikia Mahdi, Cui Weili, Pourghader Johar, Aghazadeh Sara, Ke Changhong, Miles Ronald
Department of Mechanical Engineering, Binghamton University, Binghamton, New York 13902, USA.
Division of Engineering Programs, State University of New York at New Paltz, New Paltz, New York 12561, USA.
J Acoust Soc Am. 2025 Jan 1;157(1):29-42. doi: 10.1121/10.0034788.
A study is presented of a method for creating an acoustic flow sensor that is generally compatible with current silicon microfabrication processes. An aim of this effort is to obtain a design consisting of a minimal departure from the existing designs employed in mass-produced silicon microphones. Because the primary component in all of these microphones is the cavity behind the pressure-sensing diaphragm, we begin with a study of the acoustic particle velocity within a cavity in a planar surface. The sound within the cavity is caused by the external plane sound wave traveling parallel to the cavity's open surface. It is shown that with suitable dimensions of the cavity, the acoustic particle velocity simultaneously flows inward at one end and outward at the other end of the single open cavity surface. A simple analytical model is presented to estimate the required length and depth of the cavity such that the acoustic particle velocity into and out of the opening is a reasonable approximation to that of a plane traveling sound wave in the free field. Measurements of the acoustic particle velocity into and out of the cavity are in close agreement with both the simple model and a more detailed finite element model. Agreement between two dissimilar modeling approaches and experiments suggests that the dominant features of the system have been accounted for. By redirecting the acoustic particle velocity into and out of the cavity opening rather than the flow being parallel to the plane surface, this configuration greatly facilitates the design and fabrication of structures intended to sense the acoustic flow.
本文介绍了一种用于制造声流传感器的方法，该方法通常与当前的硅微制造工艺兼容。这项工作的一个目标是获得一种设计，该设计与批量生产的硅麦克风中使用的现有设计相比，偏离最小。由于所有这些麦克风的主要组件都是压力传感膜片后面的腔体，因此我们首先研究平面表面上腔体内部的声粒子速度。腔体内的声音是由平行于腔体开口表面传播的外部平面声波引起的。结果表明，对于合适尺寸的腔体，声粒子速度在单个开口腔体表面的一端同时向内流动，在另一端向外流动。提出了一个简单的分析模型来估计腔体所需的长度和深度，使得进出开口的声粒子速度与自由场中平面传播声波的速度合理近似。对进出腔体的声粒子速度的测量结果与简单模型和更详细的有限元模型都非常吻合。两种不同建模方法与实验之间的一致性表明，该系统的主要特征已得到考虑。通过将声粒子速度导入和导出腔体开口，而不是使流动平行于平面表面，这种配置极大地促进了用于感测声流的结构的设计和制造。
