Chucui, But if "periodic boundary condition" means that all information of solution > on periodic faces pair are equal, not only the value of solution (like > Dirichlet boundary condition above), but also gradient value of solution > (like Neuman boundary condition, as normal vector is opposite, so if > grad_u_on_left = grad_u_on_right, for example, so n_left * grad_u_on_left + > n_right * grad_u_on_right, top and bottom as well) . [...] > Does deal.ii implement this kind of periodic boundary condition in fact? > Is it different from what we have done above for periodic boundary > condition like Dirichlet? > Short answer: No.
Longer answer: We identify the degrees of freedom on the respective faces with eachother. This implies treating them the same as internal faces. In case, you have a finite element that is C1-conforming this means that the ansatz space will also be C1-conforming across periodic boundary faces. However, for the standard C0-conforming FE_Q elements this only implies continuity with respect to values. In case you need continuity of the gradients across periodic faces, I would expect that you require continuity of the gradients across (internal) faces as well. Is that the case? Best, Daniel and need to choose a > > Thank you very much! > > Best, > Chucui > > > -- 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]. For more options, visit https://groups.google.com/d/optout.
