On Tue, Jun 2, 2015 at 6:00 PM, Jed Brown wrote:
> Eduardo writes:
>
> > I am solving a FEM solid mechanics linear elasticity model, for now the
> > only problem is the mesh that has needle-shaped and very flat elements.
>
> Why does it have such elements? Is the material highly anisotropic
> (
Eduardo writes:
> I am solving a FEM solid mechanics linear elasticity model, for now the
> only problem is the mesh that has needle-shaped and very flat elements.
Why does it have such elements? Is the material highly anisotropic
(e.g., fiber)? Is the geometry anisotropic (shell structures
di
Eduardo, as Matt said you problem is ill conditioned but and you might find
that if you add more elements and make the mesh less anisotropic that your
solve faster, and you get a better solution obviously.
I'm not sure what options there are for better discretization but you can
probably do a lot
On Mon, Jun 1, 2015 at 11:24 PM, Eduardo wrote:
> I am solving a FEM solid mechanics linear elasticity model, for now the
> only problem is the mesh that has needle-shaped and very flat elements.
> Have you any suggestion of preconditioner (and references).
>
The problem here is your discretizat
I am solving a FEM solid mechanics linear elasticity model, for now the
only problem is the mesh that has needle-shaped and very flat elements.
Have you any suggestion of preconditioner (and references).
Thanks,
Eduardo
On Tue, Jun 2, 2015 at 4:11 AM, Barry Smith wrote:
>
> > On Jun 1, 2015, at
> On Jun 1, 2015, at 4:06 PM, Eduardo wrote:
>
> I am solving a linear system for which the preconditioned residual decreases,
> but the true residual increases (or have an erratic behavior). According to
> Petsc FAQ, this is due to a preconditioner that is singular or close to
> singular. Wh
On Mon, Jun 1, 2015 at 4:06 PM, Eduardo wrote:
> I am solving a linear system for which the preconditioned residual
> decreases, but the true residual increases (or have an erratic behavior).
> According to Petsc FAQ, this is due to a preconditioner that is singular or
> close to singular. What c
I am solving a linear system for which the preconditioned residual
decreases, but the true residual increases (or have an erratic behavior).
According to Petsc FAQ, this is due to a preconditioner that is singular or
close to singular. What can I do in this case? I used GMRES with ILU
preconditione
