This paper studies the propagation of shear waves in a composite structure consisting of a piezoelectric layer perfectly bonded over a micropolar elastic half space. The general dispersion equations for the existence of shear waves are obtained analytically in the closed form. Some particular cases have been discussed and in one special case the relation obtained is in agreement with existing r...

Non-local fractional derivatives are generally more effective in mimicking real-world phenomena and offer precise representations of physical entities, such as the oscillation earthquakes behavior polymers. This study aims to solve 2D fractional-order diffusion-wave equation using Riemann–Liouville time-fractional derivative. The is solved modified implicit approach based on integral sense. the...

We construct and analyze a new family of rectangular (two-dimensional) or cubic (three-dimensional) mixed finite elements for the approximation of the acoustic wave equations. The main advantage of this element is that it permits us to obtain through mass lumping an explicit scheme even in an anisotropic medium. Nonclassical error estimates are given for this new element.

We study the propagation of an acoustic wave in a moving fluid in the high frequency regime. We calculate a high-frequency approximation of the solution of this problem using an Eulerianmethod. The model retained is a linearized Euler system around a mean fluid flow. For any regular mean flow, we derive a conservative transport equation for the geometrical optics approximation. We introduce the...

In a theoretical design study, we propose buried waveguides made of germanium or alloys of germanium and other group-IV elements as a CMOS-compatible platform for robust, high-gain stimulated Brillouin scattering (SBS) applications in the mid-infrared regime. To this end, we present numerical calculations for backward-SBS at 4 μm in germanium waveguides that are buried in silicon nitride. Due t...

In this paper we consider a mathematical model for photoacoustic imaging which takes into account attenuation due to thermodynamic dissipation. The propagation of acoustic (compressional) waves is governed by a scalar wave equation coupled to the heat equation for the excess temperature. We seek to recover the initial acoustic profile from knowledge of acoustic measurements at the boundary. We ...

This study was aimed at using the theory for two-dimensional phononic crystal consisting of materials with general anisotropy to calculate the band gaps phenomena in Aluminum/Barium sodium niobate (Y-cut) with hexagonal lattice and Quartz/Epoxy with square lattice phononic structures. Wave propagation properties of solids in which the periodic modulation occurs along the bounding surface has be...