For an advection-diffusion equation you have to specify boundary conditions everywhere on the boundary. You have to decide what boundary conditions you want, dirichlet, neuman, or some mixture of these. Also you have just one boundary condition for the pde, there is no separate advection boundary condition and diffusion boundary condition. Best Praveen
On Sat, 20 Jul 2019 at 4:45 PM, Sai P <[email protected]> wrote: > Hi, > > I am a new dealii user and trying to extend step 26 with an advection > term. If the method is implicit, I am not sure how to handle the boundary > terms due to upwinding boundary in the advection term. It looks like the > following code in step 26 for diffusion term will make the advection > boundary conditions redundant. > { > BoundaryValues<dim> boundary_values_function; > boundary_values_function.set_time(time); > > std::map<types::global_dof_index, double> boundary_values; > VectorTools::interpolate_boundary_values > <https://www.dealii.org/current/doxygen/deal.II/namespaceVectorTools.html#a187aeb575be07bc47cb3dea1a47aaf88> > (dof_handler, > 0, > boundary_values_function, > boundary_values); > > MatrixTools::apply_boundary_values > <https://www.dealii.org/current/doxygen/deal.II/namespaceMatrixTools.html#a9ad0eb7a8662628534586716748d62fb> > (boundary_values, > system_matrix, > solution, > system_rhs); > } > Am I missing anything? How do I handle the boundary conditions in dealii > for advection term? > > -- > 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/f8e0bffc-ec3a-43e0-8446-8febb4773397%40googlegroups.com > <https://groups.google.com/d/msgid/dealii/f8e0bffc-ec3a-43e0-8446-8febb4773397%40googlegroups.com?utm_medium=email&utm_source=footer> > . > -- 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/CAEvUdM%2BAfRaeerw6_PqjdknVjrPMQW%3D35RGhWdEgceAcyh4dxg%40mail.gmail.com.
