Hi Lorenzo,
I think the status is as follows (Dumux 3.0):
1) For the box scheme Dirichlet boundaries are always strongly enforced
so nothing special to do here.
2) For cell-centered schemes there is a new feature called "internal
Dirichlet constraints" that allows you to enforce Dirichlet constraints
in any cell. See
https://git.iws.uni-stuttgart.de/dumux-repositories/dumux/blob/master/test/porousmediumflow/1p/implicit/internaldirichlet/problem.hh
for an example (only available on the master branch).
3) For the old sequential schemes there is _no_ such feature as far as I
know (unfortunately noone had the time to implement sequential schemes
in terms of the Dumux 3.0 style solvers yet, so actually there is no
"new" sequential schemes yet, but I call it "old" because it uses Dumux
2.0 style paradigms that have been deprecated). You'd have to implement
it yourself (adapt the matrix assembly, in the simplest case just
manipulate the rows of Dirichlet dofs after everything has been
assembled, replace row with zeros set one on the diagonal and the adapt
the rhs).
That being said,
I'm not sure why you need this feature in your case. If the boundary
condition is satisfied in the first cell or on the boundary shouldn't
really matter. It's just that in the latter case you don't see the
actual boundary value in your vtk output.
It might be that there is actually something wrong with the boundaries
in the old sequential schemes. I personally don't know of any bug (and
there is no open issue on that topic), but there is always the
possibility. In that case, I would need a minimal working example how to
reproduce an actual erroneous solution (in the best case open a merge
request with the minimal working example). I'm afraid the old sequential
schemes don't get very much attention right now from the core developers.
Sorry I couldn't help more, open-source research software is always a
work in progress,
Timo
On 15.07.19 13:15, lc wrote:
Hello,
can you explain how can I strongly impose the Dirichet condition in
the first cell (or the closest one) on the inlet (left ) boundary in
order to achieve what you said, please?
I need to use 2p, sequential algorithm.
Kind regards,
Lorenzo
On 29.03.2019 16:31, Timo Koch wrote:
I mean you can also just enforce the Dirichlet value strongly in the
first cell. Then, of course it will be satisfied "cleanly". It all
depends on your discretization scheme too. For example for FEM or Box
you might have degrees of freedom directly on the boundary. Then you
can also strongly enforce them an they will always be "cleanly"
satisfied.
--
_______________________________________________________________
Timo Koch phone: +49 711 685 64676
IWS, Universität Stuttgart fax: +49 711 685 60430
Pfaffenwaldring 61 email: timo.k...@iws.uni-stuttgart.de
D-70569 Stuttgart url: www.hydrosys.uni-stuttgart.de
_______________________________________________________________
_______________________________________________
Dumux mailing list
Dumux@listserv.uni-stuttgart.de
https://listserv.uni-stuttgart.de/mailman/listinfo/dumux
