INVESTIGADORES
OLLER Sergio Horacio Cristobal
congresos y reuniones científicas
Título:
A CONSTITUTIVE THERMO MECHANICAL MODEL FOR SOLIDIFICATION PROBLEMS OF METALS
Autor/es:
D. CELENTANO; S. OLLER; E. OÑATE
Reunión:
Jornada; Journées Numériques de Besançon; 1991
Resumen:
In this paper,
the solidification process of metal pieces, modeled with the finite element method,
is described. For this purpose, a model based on the rigorous thermodynamical principles
has been developed.
As a first approach
to the problem, the following hypothesis has been adopted:
- Weak
coupling of physical a phenomenon, which implies that, the thermal and mechanical
problem are solved separately, but considering the reciprocal influence between
them.
- The
Thermal problem is studied using a temperature-based weak Galerkin formulation (which
includes the moving boundary condition) in the framework of so called fixed
domain methods. The thermal properties can depend on the temperature and the
latent heat is released in an isothermal way or in a range of temperatures,
depending of the material considered. All that phenomena, contribute to make
the problem highly nonlinear.
- The mechanical
problem is approached in the general isotropic plasticity theory frame. The
mechanical properties of the materials are temperature-dependent. Using the ?Total.
Lagrangian Formulation?, a large deformation constitutive law is formulated to
describe the different behaviors of the materials and the different states of
the solidifying metal (liquid, mushy and solid),
- The
convection effect k the liquid, as well as the heat generated by plastic
deformation, is neglected,
- A contact
model is considered.
Furthermore,
a simple solidification problem is analyzed. The numerical results are compared
with those obtained by another author.