A new class of Finitely Extensible Nonlinear Elastic (FENE-P) models obtained with a thermodynamical approach and the use of compressible natural configurations. Part II: Decoupled thermo-mechanical deformations

Abstract

In this paper which is the continuation of the isothermal viscoelastic model presented in Gomez-Constante and Palade (2023), we incorporate temperature changes into our model. To achieve this, we present a temperature dependent Helmholtz potential from where the model will be derived using the idea of evolving natural configurations. To simplify the analysis, we assume that the temperature and the invariants of deformation are decoupled so the Helmholtz potential can be expressed as the product of two independent functions. The model thus derived is consistent with fundamental thermodynamical postulates and constrains. To show its qualitative behavior we chose to compare the isothermal model in Gomez-Constante and Palade (2023) with this paper non-isothermal version of the model and show how they behave in the classical Couette flow between infinite parallel plates and analyze their differences. We also present a simple extensional flow simulation for the non-isothermal version of the model to complete the analysis. Ideas towards the following steps towards a generalization of the model are also presented and discussed.