Derivation of a Frequency Independent Criterion to Determine the Limp Model Validity for Highly Porous Sound Absorbing Materials Frequency Independent Limp Model Criterion 1
نویسندگان
چکیده
A frequency independent criterion to determine the limp model validity for highly porous sound absorbing materials is investigated. Although limp model is derived from the Biot theory assuming that the porous frame has no bulk stiffness, it is shown that this model can be used for highly porous materials since the criterion is respected. Abacus giving the criterion limit as function of the porous layer thickness are given for two configurations: sound absorption of a porous layer backed by a rigid backing and sound radiation of a plate covered by a porous layer. Its is shown that the derived criterion matches Beranek criterion but it is less restrictive.
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