Computation of viscoelastic shear shock waves using finite volume schemes with artificial compressibility

TL;DR

This paper develops and tests a finite volume computational model using artificial compressibility to simulate shear shock waves in viscoelastic solids, aiding understanding of intracranial injury mechanisms.

Contribution

It introduces a novel application of artificial compressibility in finite volume methods for modeling nonlinear shear shock waves in viscoelastic tissues.

Findings

The method accurately captures shock formation and wave focusing.

It demonstrates the applicability of the approach for nonlinear wave propagation.

The model shows good agreement with theoretical expectations.

Abstract

The formation of shear shock waves in the brain has been proposed as one of the plausible explanations for deep intracranial injuries. In fact, such singular solutions emerge naturally in soft viscoelastic tissues under dynamic loading conditions. To improve our understanding of the mechanical processes at hand, the development of dedicated computational models is needed. The present study concerns three-dimensional numerical models of incompressible viscoelastic solids whose motion is analysed by means of shock-capturing finite volume methods. More specifically, we focus on the use of the artificial compressibility method, a technique that has been frequently employed in computational fluid dynamics. The material behaviour is deduced from the Fung--Simo quasi-linear viscoelasiticity theory (QLV) where the elastic response is of Yeoh type. We analyse the accuracy of the method and demonstrate its applicability for the study of nonlinear wave propagation in soft solids. The numerical results cover accuracy tests, shock formation and wave focusing.