David, Hard to tell what's the problem here. Might be a problem with the AffineConstraints. Are they correct? Do you distribute them when you should?
Best, Bruno On Monday, February 28, 2022 at 4:12:16 PM UTC-5 [email protected] wrote: > Hello, > > I am working on PRISMS-PF (which is deal.II based) and trying to find an > issue with a corner value not being properly set. > > The problem happens when the code is finding the solution of a poisson > type equation iteratively, e.g. > > \nabla^2 \phi = f(\phi) > > I set up a 2D system, and I am using adaptive mesh. We set the initial > guess of the field \phi to a constant value everywhere. After the solution > is found, the x=y=0 node becomes zero (this is not the correct > solution), whereas the rest of the system looks fine (sea image below). > > [image: visit0001.png] > This only happens when we use adaptive mesh (not uniform). And we have > noticed that it happens if we use Neumann boundary conditions on both sides > of the corner, or a combination of Neumann and periodic BCs (we have not > tried other combinations). > > Does anyone know what may be causing this problem? > > Thank you! > > David > > -- The deal.II project is located at http://www.dealii.org/ For mailing list/forum options, see https://groups.google.com/d/forum/dealii?hl=en --- You received this message because you are subscribed to the Google Groups "deal.II User Group" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/dealii/e63cd2a0-98be-48bb-bf85-c2a4821bf1b9n%40googlegroups.com.
