Re: [Getfem-users] Computing the integral over a boundary of a given Getfem variable

[Konstantinos Poulios]

Dear David,

Assuming that you have a vectorial multiplier for contact called "mult", you can get the components of the total contact force with

FX = gf.asm_generic(mim, 0, "mult(1)", CONTACT_RG, md)
FY = gf.asm_generic(mim, 0, "mult(2)", CONTACT_RG, md)

where CONTACT_RG is the region of the mesh in which the multiplier field is defined.

To check the computed multiplier field, please try also to export the entire field to a paraview file, and show us a screenshot, if you are in doubt.

Best regards

Kostas

On Wed, Mar 16, 2022 at 6:32 PM David Danan <daviddanan9021@gmail.com> wrote:

Dear Getfem-users,

i have but a simple question.

Using Getfem, i have computed the solution of a simple contact problem (the actual geometry does not really matter).

Now, i would like to do a simple post-processing, that is, compute the integral over the contact boundary of the multiplier variable associated to the contact condition.

Using the following discussion

https://lists.nongnu.org/archive/html/getfem-users/2022-01/msg00015.html

I think i am on a good track with asm_generic but i am not sure i am actually using it correctly as i have obtained some abnormally huge values.

Could you give me the actual _expression_ to use for such a post-processing?

Thanks in advance,

kind regards,

David Danan.