Title Sound propagation in and low frequency noise absorption byhelium - filled porous material
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Sound propagation in and low frequency noise absorption by helium-filled porous material.
Low-frequency noise is difficult to deal with by traditional porous material due to its inherent high acoustic impedance. This study seeks to extend the effective range of sound absorption to lower frequencies by filling a low density gas, such as helium, in the porous material. Compared with conventional air-filled absorption material, the helium-filled porous material has a much reduced chara...
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تاریخ انتشار 2009