A straightforward criterion to determine the limp model validity for porous materials is addressed here. The limp model is an "equivalent fluid" model which gives a better description of the porous behavior than the well known "rigid frame" model. It is derived from the poroelastic Biot model assuming that the frame has no bulk stiffness. A criterion is proposed to identify the porous materials...

In this paper, we present a fractal (self-similar) model of acoustic propagation in porous material with rigid structure. The medium is modeled as continuous non-integer spatial dimension. basic equations acoustics are written. model, the fluid space considered while solid matrix non-fractal. fluid–structure interactions described by fractional operators time domain. resulting equation contains...

The paper presents numerical analysis – involving an advanced multiphysics modeling – of the concept of active porous composite sound absorbers. Such absorbers should be made up of a layer or layers of poroelastic material (porous foams) with embedded elastic inclusions having active (piezoelectric) elements. The purpose of such active composite material is to significantly absorb the energy of...