Author(s): Jaouen Luc, Gourdon Emmanuel, Edwards Matthew
In this communication, we present a technique to estimate the 6 parameters of the Johnson-Champoux-Allard-Lafarge model for porous media using a classical impedance tube.\n\nThe estimation of the static air-flow resistivity is obtained from the imaginary part of the dynamic mass density as proposed by Panneton & Olny. The open porosity is estimated from the real part of the bulk modulus and the 4 remaining parameters (the high frequency limit of the dynamic tortuosity, the viscous & thermal characteristic lengths and the static thermal permeability) are estimated using the analytical inversion proposed by Panneton & Olny.\n\nExamples of characterizations using various materials are presented. In particular, it is shown how to estimate the dynamic mass density and the dynamic bulk modulus from 2-microphone or 3-microphone impedance tubes and how it leads to the estimation of the 6 parameters one after the other.
Name: Dr Luc Jaouen