Green’s functions resulting from wave propagation in a single-layer porous isotropic foam with finite thickness

Authors

Department of Mechanical Engineering, University of Tabriz, Tabriz, Iran.

Abstract

In this paper, the green’s functions resulting from wave propagation in a porous isotropic foam monolayer with the boundary condition of the foam end as a rigid-bonded are investigated. This article aims to obtain the stresses and displacements resulting from wave propagation of harmonic forces located on isotropic foam. Foams are of the saturated porous material type due to the hollow pores in which fluid moves. The governing equations of wave propagation for saturated porous material are complex partial differential equations converted into two separate equations using two unknown potential functions. The obtained equations are transformed into simpler equations using Henkel integral and Fourier series transformations. By utilizing the governing boundary condition of the problem, two unknown potential functions are obtained in the transformed space, and with Henkel's integral inverse operations, the resulting solution is obtained in the frequency space. One of the most important results of this study is that in the real part of Green’s functions, point loading causes maximum stress and displacement in the vertical direction. Ring load and low porosity have the maximum frequency angle from the wave propagation in Green’s functions.

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Main Subjects


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