Dear Irene,
I understand that the surface of the sphere is not conforming to the mesh
of the cube, right?
So you want to impose no-slip boundary conditions through the mesh of the
cube.
I know two ways to do it.
One through pure fictitious domain method, and the other through
fictitious domain method with XFem.
For the second you can look into implementation of
contrib/xfem_contact/xfem_dirichlet.cc
(you can find it in your Getfem installation).
Pure fictitious domain method (with LS integration, as you mentioned it) is
described in detail in:
Legay A, Chessa J, Belytschko T. An Eulerian–Lagrangian method for fluid
structure interaction based on level sets.
Computer Methods in Applied Mechanics and Engineering 2006;
195(17–18):2070–2087.
It's also possible to implement it in Getfem as well. A similar Level set
based fictitious domain contact algorithm exists in Getfem and you can see
the example of it usage in contrib/level_set_contact (it has a reference to
the corresponding article inside)
Regarding the post-processing, I think you should use the technique of
slices, as it's used in XFem examples of Getfem (although I've never used
it myself).
Best regards,
Andriy
On 22 January 2014 10:30, ing.ire <[email protected]> wrote:
> Hello,
> I'm using getfem to solve Stokes problem in a cube (as in
> tests/stokes.cc), but I want to put a sphere inside the cube, as if it was
> a solid particle in a volume of fluid, so I don't want to solve stokes
> inside the sphere. I'm using level-sets to cut the mesh and the option
> INTEGRATE_OUTSIDE to solve the problem only outside the region cut by the
> level set function.
> How can I set no-slip boundary conditions on the sphere, i.e. Dirichlet
> condition?
> Is there any way to export the cut mesh in vtk? I tried with
>
> getfem::vtk_export vtkp("stokes.vtk");
> vtkp.exporting(mfls);
> vtkp.write_mesh();
>
> where mfls is a mesh_fem_level_set object, but loading the stokes.vtk file
> in paraview I see the whole mesh, and no sign of the cut.
>
> Thank you in advance.
> Irene
>
> _______________________________________________
> Getfem-users mailing list
> [email protected]
> https://mail.gna.org/listinfo/getfem-users
>
>
_______________________________________________
Getfem-users mailing list
[email protected]
https://mail.gna.org/listinfo/getfem-users
