Modelling of nonlinear wave scattering in a delaminated elastic bar

TL;DR

This paper models how nonlinear waves interact with delaminations in layered elastic bars, demonstrating that wave fission can be used to detect structural defects effectively.

Contribution

It introduces a semi-analytical numerical approach based on asymptotic expansions and integrability theory to analyze nonlinear wave scattering in delaminated structures.

Findings

Delamination causes fission of incident solitary waves

Numerical results agree with analytical predictions

Wave behavior can be used for defect detection

Abstract

Integrity of layered structures, extensively used in modern industry, strongly depends on the quality of their interfaces; poor adhesion or delamination can lead to a failure of the structure. Can nonlinear waves help us to control the quality of layered structures? In this paper we numerically model the dynamics of a long longitudinal strain solitary wave in a split, symmetric layered bar. The recently developed analytical approach, based on matching two asymptotic multiple-scales expansions and the integrability theory of the KdV equation by the Inverse Scattering Transform, is used to develop an effective semi-analytical numerical approach for these types of problems. We also employ a direct finite-difference method and compare the numerical results with each other, and with the analytical predictions. The numerical modelling confirms that delamination causes fission of an incident solitary wave and, thus, can be used to detect the defect.