Šimonová Karina, Honzík Petr
Faculty of Transportation Sciences, Czech Technical University in Prague, Konviktská 20, 110 00 Praha, Czech Republic.
Micromachines (Basel). 2023 Apr 24;14(5):921. doi: 10.3390/mi14050921.
Microfabricated electroacoustic transducers with perforated moving plates used as microphones or acoustic sources have appeared in the literature in recent years. However, optimization of the parameters of such transducers for use in the audio frequency range requires high-precision theoretical modeling. The main objective of the paper is to provide such an analytical model of a miniature transducer with a moving electrode in the form of a perforated plate (rigid elastically supported or elastic clamped at all boundaries) loaded by an air gap surrounded by a small cavity. The formulation for the acoustic pressure field inside the air gap enables expression of the coupling of this field to the displacement field of the moving plate and to the incident acoustic pressure through the holes in the plate. The damping effects of the thermal and viscous boundary layers originating inside the air gap, the cavity, and the holes in the moving plate are also taken into account. The analytical results, namely, the acoustic pressure sensitivity of the transducer used as a microphone, are presented and compared to the numerical (FEM) results.
近年来，文献中出现了带有穿孔动板的微制造电声换能器，其用作麦克风或声源。然而，要优化此类换能器在音频范围内使用的参数，需要高精度的理论建模。本文的主要目的是提供一种微型换能器的分析模型，该换能器具有穿孔板形式的动电极（在所有边界处刚性弹性支撑或弹性夹紧），由围绕小气腔的气隙加载。气隙内声压场的公式能够表达该场与动板位移场以及通过板上孔的入射声压之间的耦合。还考虑了气隙、腔以及动板上孔内部产生的热边界层和粘性边界层的阻尼效应。给出了用作麦克风的换能器的声压灵敏度的分析结果，并与数值（有限元法）结果进行了比较。
