As always there is a "deal.ii" way of doing the calculations.
The FEValues::get_function_gradients() is actually what I needed.
I got a little bit confused with the FEValues::get_normal_vectors(). This
seems to return the normal direction of the face and doesn't give any
further info about the
Giorgos,
You can find a discussion for how constraints are handled in deal.II in
https://www.dealii.org/developer/doxygen/deal.II/group__constraints.html.
Thank you for your feedback.
> I'll try to explain what I try to calculate with the help of a standard
> FEM textbook:
>
> [...]
>
> In the
Thank you for your feedback.
I'll try to explain what I try to calculate with the help of a standard FEM
textbook:
[image: CaptureFEMbook.PNG]
In the book the global system is partitioned so that the first row contains
the known U1 dofs and the second row the unknown the dofs U2.
They solve
> In my case I solve a simple laplace problem, that represent groundwater flow
> with non zero dirichlet boundary conditions
> My goal is to estimate how much water comes in and out from the dirichlet BC
> nodes.
You're asking the wrong question. What you are looking for is a *flux*, which
This is a year old post but I'm dealing with the same issue so I decided to
continue here instead creating a new one.
In my case I solve a simple laplace problem, that represent groundwater
flow with non zero dirichlet boundary conditions
My goal is to estimate how much water comes in and out
On 08/01/2018 03:34 PM, RAJAT ARORA wrote:
If I understand correctly, I dont think that will work. The reason is
because of the Dirichlet boundary conditions, the value of the rhs at those
nodes is unknown until you solve for the system.
I think it's unclear to me what exactly you want in
> However, now how do I get the value of the rhs at the nodes where DBC were
> specified?
So, are you wanting the values to which the DoFs on the Dirichlet boundary are
going to be prescribed? This is the same as the values stored in the constraint
matrix (assuming that it holds only
Hi Jean,
Thanks for your reply.
If I understand correctly, I dont think that will work. The reason is
because of the Dirichlet boundary conditions, the value of the rhs at those
nodes is unknown until you solve for the system.
On Wednesday, August 1, 2018 at 10:08:12 AM UTC-4, Jean-Paul
