Elastic wave scattering in porous unidirectional fiber-reinforced composites

Scattering of elastic waves in unidirectional fiber-reinforced porous-matrix composites is studied using novel features of Biot classic model for dynamic poroelasticity. The method of separation of variables along with the appropriate wave field expansions, the pertinent boundary conditions, and the translational addition theorems for cylindrical wave functions are employed to develop a closed-form solution in form of infinite series. The analytical results are illustrated with numerical examples in which a pair of rigid or elastic fibers are insonified by a plane fast compressional or shear wave at end-on/broadside incidence. The effects of incident wave frequency, proximity of the two fibers, fiber material properties and angle of incidence on the far-field backscattered radial and shearing stress amplitudes are examined. Particular attention has been focused on multiple scattering interactions in addition to the slow wave coupling effects which is known to be the primary distinction of the scattering phenomenon in poroelasticity from the classical elastic case. Limiting cases are considered and fair agreements with well-known solutions are established.