Transmission of ultrasonic waves through porous layers of high flowresistivity saturated by air

摘要

Transmission of ultrasonic waves through porous materials of highnflow resistivity and porosity (in contact with air at both faces) isnmodelled and measured for an open-bubble foam at normal and obliquenincidence. The importance of the airborne wave and the differences withnthe case of an elastic nonporous solid are demonstrated. A simple methodnto measure the shear modulus and the Poisson coefficient of the frame isnsuggested for similar materials