English

On the thermodynamic consistency of Quasi-Linear Viscoelastic models for soft solids

Soft Condensed Matter 2021-04-26 v1

Abstract

Originating in the field of biomechanics, Fung's model of quasi-linear viscoelasticity (QLV) is one of the most popular constitutive theories employed to compute the time-dependent relationship between stress and deformation in soft solids. It is one of the simplest models of nonlinear viscoelasticity, based on a time-domain integral formulation. In the present study, we consider the QLV model incorporating a single scalar relaxation function. We provide natural internal variables of state, as well as a consistent expression of the free energy to illustrate the thermodynamic consistency of this version of the QLV model. The thermodynamic formulation highlights striking similarities between QLV and the internal-variable models introduced by Holzapfel and Simo. Finally, the dissipative features of compressible QLV materials are illustrated in simple tension.

Keywords

Cite

@article{arxiv.2012.01811,
  title  = {On the thermodynamic consistency of Quasi-Linear Viscoelastic models for soft solids},
  author = {Harold Berjamin and Michel Destrade and William J. Parnell},
  journal= {arXiv preprint arXiv:2012.01811},
  year   = {2021}
}