Effects of memory response and impedance barrier on reflection of plane waves in a nonlocal micropolar porous thermo-diffusive medium

This research problem is an investigation of reflection amplitude in a nonlocal porous-thermo-micropolar diffusion half-space under memory dependent derivative (MDD) thermo-elasticity subjected to impedance boundary reflecting surface. The governing equations for nonlocal porous-thermo-micropolar diffusion medium in MDD theory are formulated. This research challenge is solved analytically for a two-dimensional model in order to demonstrate the presence of four coupled longitudinal waves and two paired transverse waves denoted as coupled longitudinal displacement wave (cLDW-I), coupled longitudinal thermal wave (cLDW-II), coupled longitudinal mass diffusion wave (cLDW-III), coupled longitudinal void volume fraction wave (cLDW-IV), and coupled transverse displacement wave (cTDW) and coupled transverse micro-rotational wave (cTMW). When there is nonlocality, diffusion, and porous characteristics in the medium, it is discovered to have an impact on these coupled longitudinal waves, making them dispersive and attenuating. The transverse wave is non-attenuating but dispersive, it is unaffected by diffusion and porous characteristics. To find the expression for the reflection coefficients of reflected waves, the plane wave reflection from a thermally insulated surface subjected to an impedance boundary is explored. For a specific material, the reflection coefficients of the reflected waves are calculated, and graphic representations of the fluctuations of the reflection coefficients versus the incidence angle, nonlocality, diffusion and porous constants are provided. For further investigation, energy ratio can be studied in future.