Slow waves, surface waves and their applications

Keith Attenborough , Imran Bashir , Ho-Chul Shin , Shahram Taherzadeh

Fluid-saturated porous elastic solids support two compressional wave types, often called 'fast' and 'slow', and a shear wave. Walter Lauriks recognised the commonality of the physical mechanisms which govern the acoustical properties of such media and initiated a great many studies ranging from the acoustical monitoring of marrow filled bone to properties of air-filled bread, soils and snow. The Biot parameter values that create distinct slow waves in transmission experiments are explored. There are two types of surface waves at a poroelastic boundary: a fluid-coupled Rayleigh wave and a wave that depends on the surface impedance. A rough hard surface is also able to generate an acoustic surface wave. Walter Lauriks studied pore-related surface waves and those over a periodically-rough hard surfaces. It is shown that propagation over hard-backed square lattice grating layers modelled previously using modal analysis can be described as that over a square pore layer. Similarly propagation over rectangular grooves or bosses also modelled previously using modal analysis can be modelled as that over a slit pore layer.

Mots clés: slow waves; surface waves; poroelastic media

Domaines: Acoustique [physics.class-ph]

Keith Attenborough, Imran Bashir, Ho-Chul Shin, Shahram Taherzadeh. Slow waves, surface waves and their applications. Acoustics 2012, Apr 2012, Nantes, France. ⟨hal-00810598⟩