It seems my images were not rendered -- here they are in order as attachments.
On Thu, Dec 17, 2020 at 10:56 PM Corbin Foucart <[email protected]> wrote: > I have a problem with direction-dependent diffusion (that is, the > diffusivity \nu depends on the derivative direction but not spatial > location) such that the horizontal diffusivity and vertical diffusivity are > different, leading to a Laplacian as follows: > > > I am discretizing the problem with a mixed method, which defines the > auxiliary variable L = ∇u such that > > > So in my weak form, I end up with terms like the following: > (please excuse the abuse of index notation with repeated j three times). > phi_ij here refers to each scalar basis function in the tensor-valued > finite element space. > > It seems using the deal.ii FEValuesExtractors, I can access the divergence > of each tensor-valued basis function, but I need to multiply each term in > the divergence with the appropriate value of \nu by component. > > I suppose I could ask for the gradient of each phi and do the sum > manually,but I was wondering if there's a way to do it directly. Is there a > standard way of doing this in deal.ii? > > Any pointers would be appreciated! > > -- > 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 a topic in the > Google Groups "deal.II User Group" group. > To unsubscribe from this topic, visit > https://groups.google.com/d/topic/dealii/ptfmuBKUoiA/unsubscribe. > To unsubscribe from this group and all its topics, send an email to > [email protected]. > To view this discussion on the web visit > https://groups.google.com/d/msgid/dealii/65594873-33d7-44c2-834b-ba398fd9fb1bn%40googlegroups.com > <https://groups.google.com/d/msgid/dealii/65594873-33d7-44c2-834b-ba398fd9fb1bn%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/CAE%2BMPodoB41SAR8UrJHq_cNDhCqed1cKxtQNr%3DZ-Q5UBgk4syQ%40mail.gmail.com.
