Re: Problem with dirichlet condition and source term

[Konstantinos Poulios]

Dear Benjamin,

A source term corresponds to a Neumann BC. So the [0,1,0] vector that you apply is a actually a traction, not a displacement. You need to apply a non-homogeneous Dirichlet condition if you want to enforce a displacement of [0,1,0] at the top surface.

BR

Kostas

On Mon, Aug 2, 2021 at 3:17 PM BLANCKAERT Benjamin <Benjamin.BLANCKAERT@entpe.fr> wrote:

Dear Getfem Users,

I am doing an internship in which I try to modelize a simple case of soil reinforced with rigid inclusions but I have a problem with the interaction between the source term I apply and the dirichlet conditions. I explain :

I apply Dirichlet Condition in the 4 corner at the bottom of my model in the simplest way : md.add_Dirichlet_condition_with_multipliers(mim,'u',mfu,CORNER) (I use Python module)

I also add a source_term_brick at the top of my model, here an example with an unit displacement:

d = [0,1,0]

md.add_initialized_data('d',d)

md.add_source_term_brick(mim, 'u', 'd',TOP)

When I visualize the results with paraview I don't have the expected results. Indeed the displacement at the TOP is 2.2E-6 (which is very far from 1). 

I tried to identify the problem and I am almost sure that it is a problem with the dirichlet conditions which spread too much. 

Do you have any idea about How to fix it ? 

/// Blanckaert Benjamin