Acoustical and mechanical characterization of anisotropic open-cell foams

Acoustical (viscous static permeability, tortuosity, and viscous characteristic length) and mechanical (skeleton viscoelasticity tensor) parameters which characterize the behavior of porous media are provided from measurements along three perpendicular axes. The measurements are performed on cubic samples of open-cell foams. The longitudinal direction is chosen to be parallel to the growth direction of the foam. The results show that the samples tested here exhibit a quasi-axisymmetrical geometry. It appears that a precise description of this type of reticulated polymeric foam must include its anisotropy, especially for vibroacoustic behavior prediction.