On the development of an acoustic permeameter to determining the mean Darcy permeability for porous tissue scaffolds

The measurement procedure introduced in the ISO Standard 9053-2:2020 allows to determine the airflow resistance in a wide range of porous and permeable materials, by applying a pressure wave-drop method. Flow resistivity is an intrinsic property of porous materials, related to the permeability, as defined by Darcy, and to the hydraulic conductivity. Consequently, once the airflow resistivity of any porous material is known (independently of the fluid flow properties, such as viscosity and density), it is possible to determine other transport properties and characteristics widely used in various application fields. In this work, the development and the application of an accurate sub-infrasonic “acoustic permeameter” (developed and realized at INRIM) are described, and some practical examples, related to the determination of the Darcian permeability for porous scaffold, used in tissue engineering, are illustrated.