Noise Reducing Materials and Structures
Ultrasonic characterisation of porous materials, by Philippe Leclaire (University of Burgundy) Dec. 4, 2017
DENORMS Action's Training School "Experimental techniques for acoustic porous materials and metamaterials", Le Mans, 4-6th December 2017
Lecturer: Philippe Leclaire (University of Burgundy)
Acoustic models of the acoustics of porous and perforated media involve a set of physical parameters. Some of the parameters, the tortusity, the viscous and thermal characteristic lengths are defined for a perfect incompressible and inviscid fluid saturating the porous medium. It is shown that ultrasonic propagation in air-saturated materials can be used to determine these parameters. A basic method involving air-coupled ultrasonic transducers is presented. Variants of this method and a practical implementation of one of these is proposed.