A generalized fractional-order elastodynamic theory for non-local attenuating media

Abstract

This study presents a generalized elastodynamic theory, based on fractional-order operators, capable of modelling the propagation of elastic waves in non-local attenuating solids and across complex non-local interfaces. Classical elastodynamics cannot capture hybrid field transport processes that are characterized by simultaneous propagation and diffusion. The proposed continuum mechanics formulation, which combines fractional operators in both time and space, offers unparalleled capabilities to predict the most diverse combinations of multiscale, non-local, dissipative and attenuating elastic energy transport mechanisms. Despite the many features of this theory and the broad range of applications, this work focuses on the behaviour and modelling capabilities of the space-fractional term and on its effect on the elastodynamics of solids. We also derive a generalized fractional-order version of Snell’s Law of refraction and of the corresponding Fresnel’s coefficients. This formulation allows predicting the behaviour of fully coupled elastic waves interacting with non-local interfaces. The theoretical results are validated via direct numerical simulations.

Document Details

Document Type
Pub Defense Publication
Publication Date
Jun 01, 2020
Source ID
10.1098/rspa.2020.0200

Entities

People

  • Fabio Semperlotti
  • Sansit Patnaik

Organizations

  • Defense Advanced Research Projects Agency
  • National Science Foundation
  • Purdue University

Tags

Fields of Study

  • Mathematics

Readers

  • Computational Fluid Dynamics (CFD)
  • Structural Dynamics.
  • Wave Propagation and Nonlinear Chaotic Dynamics.

Technology Areas

  • Space