Transmission of ultrasonic waves through porous materials of high flow resistivity and porosity (in contact with air at both faces) is modelled and measured for an open-bubble foam at normal and oblique incidence. The importance of the airborne wave and the differences with the case of an elastic nonporous solid are demonstrated. A simple method to measure the shear modulus and the Poisson coefficient of the frame is suggested for similar materials.
Published in:
Ultrasonics, Ferroelectrics and Frequency Control, IEEE Transactions on
(Volume:46
,
Issue:
1
)
Date of Publication: Jan. 1999