Influence of fiber orientation on reflection and attenuation phenomenon in fiber-reinforced viscoelastic medium

Available studies on the reflection phenomenon in fiber-reinforced media assert the inclination of fibers along the coordinate axis and incidence of homogeneous wave. But the medium being anisotropic, the waves propagating in a fiber-reinforced medium are inhomogeneous in nature. Arbitrary and normal inclinations of fibers with the coordinate axes result in monoclinic and transverse isotropy symmetries within the medium, respectively. These generate varying geometries in composites. So, the present study discusses the reflection phenomenon of three-dimensional attenuated waves at the plane boundary of a fiber-reinforced viscoelastic medium (FRVM). Attenuated wave propagation is governed by a complex slowness vector, whose components along and perpendicular to the propagation direction define the propagation and attenuation vectors. The attenuation vector is resolved to get homogeneous/inhomogeneous attenuations. The angle deviation between attenuation and propagation vectors represents inhomogeneous waves. Inhomogeneous wave incidence at the stress-free surface generates three reflected waves. Generalized Snell’s law is used to find the slowness vectors of the reflected waves. The decomposition of the slowness vector yields different characteristics of reflected waves. The energy matrix is calculated for energy partition among the reflected waves at the boundary. A numerical example is considered to study the effect of the prevalent parameters on the characteristics of reflected waves.