Numerical Performance Of A Mixed Stabilized Finite Element Technology For Solid Mechanics. Parallel Implementation.

Abstract

In this work, a mixed stabilized formulation based on the orthogonal sub-grid scale
method, is evaluated. The approach considers linear interpolation for displacement and pressure
variables. The numerical analysis is particularly addressed to test the formulation behavior
under kinematical incompressibility constraints, such as incompressible elasticity problems,
limit load determination or strain localization in standard isochoric plasticity models.
The stabilized scheme is implemented in PETSc-FEM parallel finite element code. A novel
preconditioner is used to solve the iterative linear system, comparing its convergence properties
with other classical widely used preconditioner.
J2 plasticity model is used as the constitutive law for the proposed examples. The numerical
results are compared with standard Galerkin elements and with an alternative stabilized mixed
formulation based on pressure stabilized Petrov-Galerkin method.