Absorption characteristics of a double‐leaf membrane with an absorptive layer in its cavity
Absorption characteristics of a double‐leaf membrane with an absorptive layer in its cavity
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DOI：
10.1121/1.422830
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发表时间：
1998-05
影响因子：
2.4
通讯作者：
K. Sakagami;T. Uyama;M. Kiyama;M. Morimoto
中科院分区：
文献类型：
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作者：
K. Sakagami;T. Uyama;M. Kiyama;M. Morimoto
从理论上分析了在腔中有吸收层的双叶膜的吸收特性。双叶膜被建模为两个无限膜，它们之间有一个空腔，由三层任意介质组成。该理论还包括了内叶渗透性的影响。通过数值算例讨论了吸收层参数对吸收特性的影响。不渗透双叶膜的吸收特性在低频处表现为质量弹簧共振峰。随着吸收层厚度的增加，该峰变大并移向较低的频率。在可渗透的情况下，吸收特性与常规多孔吸收剂相似；在低频时吸收率低，在高频时吸收率高。随着吸收层厚度的增加，吸收在所有频率上都变得更高。吸收层位置的变化会影响双叶膜的吸收特性。这种效应与腔内驻波声场有关。吸附层的流动阻力有一个最佳值，可以最大限度地提高双叶膜的吸收率。
Absorption characteristics of double‐leaf membranes with an absorptive layer in the cavity are theoretically analyzed. The double‐leaf membrane is modeled as two infinite membranes with a cavity between them, which consists of three layers of arbitrary media. The theory also includes the effect of permeability of the interior leaf. The effects of parameters of the absorptive layer on the absorption characteristics are discussed through numerical examples. The absorption characteristics of an impermeable double‐leaf membrane are characterized by a mass‐spring resonance peak at low frequencies. This peak becomes larger and shifts to lower frequencies as the thickness of the absorptive layer increases. The absorption characteristics are, in permeable cases, similar to those of the conventional porous absorbents; the absorption is low at low frequencies and higher at high frequencies. As the thickness of the absorptive layer increases, the absorption becomes higher at all frequencies. The change in position of the absorptive layer affects the absorption characteristics of the double‐leaf membrane. This effect is related to the standing‐wave sound field in the cavity. The flow resistance of the absorptive layer has an optimum value to maximize the absorption of a double‐leaf membrane.