Dispersion analysis in a 3D lattice elastic waveguide for the design of an absolute filter

Abstract

This study presents a method for analyzing and designing elastic waveguides using 3D printed periodic truss structures to control the propagation of elastic waves. We propose an algorithm, based on the application of Bloch boundary conditions on a beam spectral model, to perform fast and efficient extraction of the full wave dispersion. Thanks to symmetry arguments, we introduce an identification method allowing for a better understanding of the dispersion. We then apply this method to a case study and demonstrate how it can be used to identify and design a structure exhibiting broadband absolute forbidden gaps.