SOUND-PROPAGATION IN AIR-SATURATED RANDOM PACKINGS OF BEADS

In the pore space of packed grain material, transport properties are c haracterized by macroscopic parameters. Some of them, tortuosity, char acteristic dimensions, viscous permeability, and trapping constant, ar e measured for a random packing of glass beads and compared to evaluat ions performed in previous studies. These parameters are used to predi ct the surface impedance at normal incidence of a layer of glass beads . The predictions are compared to measurements performed at normal inc idence in a Kundt tube. (C) 1998 Acoustical Society. of America. [S000 1-4966(98)04610-4]