A Low Frequency Sound Absorber with Multiple Magnetic Negative Stiffness Cells
نویسندگان
چکیده
A membrane absorber with single magnetic negative stiffness cell usually can achieve a thin layer sound absorption for one absorption peak at low-frequency. In this paper a sound absorber with multiple magnetic negative stiffness cells was designed to realize a compact design for low frequency sound absorption. This absorber comprises three cells or more in which exists different magnetic negative stiffness. And the electro-acoustic analogy model of this absorber for three cells face the incident wave in parallel is present to calculate the total impedance and predict its absorption performance. The multiple frequencies sound absorber is capable of unity absorption at multiple frequencies and broad bandwidth, due to the regime of different magnetic negative stiffness. This has been well demonstrated by equivalent circuit simulation results in this paper.
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