Modelling of the acoustic radiation of a structure covered by a porous layer
نویسنده
چکیده
To predict noise in enclosure containing treated vibrating panels, porous layer effect has to be taken into account. This study propose an analytical model of the effects of a porous layer on a vibrating plate by separating the acoustical and vibratory behaviours. This paper deals with acoustic coupling by means of surface impedance derived by a one-dimensional model using ”Biot-Allard” theory. It is shown that this impedance is different from that calculated when the porous is backed by an impervious rigid wall. The total radiation efficiency of a circular plate characterized by the surface impedance, clamped in a rigid infinite baffle, is computed and compared with experimental measurements. This model shows good agreement with experimental datas.
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