A Mixed Temperature/heat Flux Formulation for Solving Unsteady Thermal Problem. Application to Hot Forming Process Simulation

Elisabeth Massoni (1) , Céline Pelissou (1) , Jean-Loup Chenot (1)

1 CEMEF - Centre de Mise en Forme des Matériaux

The thermal analysis using standard linear tetrahedral finite elements may be affected by spurious local extrema in the regions affected by thermal shocks, in such a severe way to discourage the use of these elements. The present work proposes a mixed continuous temperature/heat flux formulation to solve the unsteady thermal problem. This new numerical model should allow to improve the thermomechanical coupling effects during the simulation of 3D forming processes (for example during hot or cold forging processes and during heat treatment. The spatial model is based on the Galerkin approach with the linear tetrahedral P1/P1 mixed finite elements. Time integration is based on an implicit scheme. The performance of this method is evaluated by means of test case with analytical solution, as well as an industrial application, for which a well-behaved numerical solution is available, and by comparisons with two discontinuous Galerkin : the explicit Taylor Discontinuous Galerkin scheme, DTG (P0/P0 interpolation and third degree Taylor time integration) and the implicit Discontinuous Galerkin model, IMPGD (P0/P0+ interpolation with implicit Euler scheme). For this study, the 3D finite element FORGE3® software is required.

Mots clés: unsteady thermal problem; finite element; mixed formulation; linear interpolation; implicit time integration; discontinuous Galerkin; thermal shock; hot forging

Domaines: Matériaux

Elisabeth Massoni, Céline Pelissou, Jean-Loup Chenot. A Mixed Temperature/heat Flux Formulation for Solving Unsteady Thermal Problem. Application to Hot Forming Process Simulation. 8th International Conference on Computational Plasticity CIMNE UPC, Sep 2005, Barcelona, Spain. ⟨hal-00509838⟩