Journal of Theoretical
and Applied Mechanics

50, 1, pp. 3-22, Warsaw 2012

Theoretical and numerical aspects in weak-compressible finite strain thermo-elasticity

Ahmad-Wahadj Hamkar, Stefan Hartmann
In this essay, a constitutive model for nearly incompressible elastic behavior is extended to the case to thermal effects. First, the use is made of the multiplicative decomposition of the deformation gradient into a thermal and a mechanical part. The thermal part is purely volumetric. Additionally, the mechanical part is multiplicatively decomposed into a volume-preserving and a volume-changing part so that the final stress state shows the influences of the temperature-dependence. The proposed model is carefully studied in view of the thermo-mechanical coupling effects. Second, the model is implemented into a time-adaptive finite element formulation based on higher-order Rosenbrock-type methods, which is a completely iteration-free procedure so that really fast computations are available. The article concludes with a three-dimensional numerical simulation of a representative elastomeric tensile specimen.
Keywords: thermoelasticity; finite strains; finite elements; Rosenbrock- -type methods