A space-time discretization of a nonlinear peridynamic model on a 2D lamina

TL;DR

This paper introduces a spectral space-time discretization method for a nonlinear 2D peridynamic model, combining Fourier-based spatial discretization with the Newmark-$eta$ time integration, and validates it through convergence, stability, and numerical tests.

Contribution

It presents a novel spectral discretization approach for nonlinear peridynamics in 2D, with convergence analysis and techniques to handle boundary conditions.

Findings

Convergence of the fully discrete approximation is established.

The method demonstrates stability for the linear peridynamic model.

Numerical tests validate the accuracy and effectiveness of the approach.

Abstract

Peridynamics is a nonlocal theory for dynamic fracture analysis consisting in a second order in time partial integro-differential equation. In this paper, we consider a nonlinear model of peridynamics in a two-dimensional spatial domain. We implement a spectral method for the space discretization based on the Fourier expansion of the solution while we consider the Newmark-$\beta$ method for the time marching. This computational approach takes advantages from the convolutional form of the peridynamic operator and from the use of the discrete Fourier transform. We show a convergence result for the fully discrete approximation and study the stability of the method applied to the linear peridynamic model. Finally, we perform several numerical tests and comparisons to validate our results and provide simulations implementing a volume penalization technique to avoid the limitation of periodic boundary conditions due to the spectral approach.