Anup, I am trying to implement the periodic boundary condition for a nonlinear > parabolic equation (scalar). > I have considered a *parallelepiped *as shown in the attached pdf. I want > to impose periodic > BC at x=0 and x=w surfaces. I have used an offset vector as appearing in > the piece of code > below, which I formed based on my understanding from the documentation (it > is tangential to the > surface x = w). Could you please tell > me if it is the correct expression. I think the problem is in this vector > only, because when I reduce the > angle theta to zero, it works. Boundary x =0 and x=w are numbered as 1 and > 11, respectively. > I also tried with the offset vector : Tensor<1, dim>(0., 0., - > w*tan(theta)) > Any suggestion and help would be appreciated. > > constraints_eta1.clear(); > std::vector<GridTools::PeriodicFacePair<typename > DoFHandler<dim>::cell_iterator> > periodicity_vector1; > GridTools::collect_periodic_faces(dof_handler_eta, 1, 11, 0, > periodicity_vector1, > Tensor<1, dim>(0., 0., w*tan(theta))); > > DoFTools::make_periodicity_constraints<DoFHandler<dim> > >(periodicity_vector1, constraints_eta1); > constraints_eta1.close(); > That looks and sounds correct if the vertices of the bounding parallelepiped have the coordinates (0|0|0), (w|0|tan(theta)*w), (0|h|0), (w|h|tan(theta)*w), (0|0|L), (w|0|L+tan(theta)*w), (0|h|L), (w|h|L+tan(theta)*w)
Can you confirm that the coarse cells have the correct boundary indicators? Would you have a minimal code? Best, Daniel -- 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 dealii+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
