Hello,
> for solving the (ideal) MHD equations, I would like to implement two custom >> shapesets: >> > > By "shapeset" do you mean "set of shape functions"? > Exactly. > > > * one for the flow part, completely discontinuous, scalar FE space, >> analogy >> to FE_DGQ, but based on Taylor expansion in the cell center >> >> o this should be the easy part, but I would like to ask how to go >> about >> it in deal.ii - I would like to implement at least linear and >> quadratic functions >> > > Do you do the Taylor expansion in real space, or on the reference cell and > then map to real space? > > If the former, I think you will want to look at the implementation of the > FE_DGP and FE_DGP_Monomial classes, of which at least one does something > similar IIRC. > In real space, thank you, will look at that. > > > * one for the magnetic field, a vector Hdiv space, analogy to >> FE_RaviartThomas, but in this case a space of divergence-free >> functions >> that satisfy div F = 0 within the reference cell >> o this I assume will be more difficult, but here I am only after >> linear >> functions >> > > Again: on the reference cell or in real space? > > If you work in real space, then in 2d there are 2x3 basis functions for > the linear space (two vector components, each of which has the form > a+bx+cy), of which you can eliminate one because of the divergence > constraint, if I count correctly. > > If you map from the reference cell, but require that div u = 0 pointwise > in real space, then things may be more complicated. > Here I have no preference, whichever is an easier way to satisfy div u = 0 pointwise. I will take a look at the implementation you mentioned, thanks. > > Best > Wolfgang > > -- > ------------------------------------------------------------------------ > Wolfgang Bangerth email: [email protected] > www: http://www.math.colostate.edu/~bangerth/ > > > -- > The deal.II project is located at http://www.dealii.org/ > For mailing list/forum options, see https://groups.google.com/d/fo > rum/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/to > pic/dealii/NDiUu3qESOM/unsubscribe. > To unsubscribe from this group and all its topics, send an email to > [email protected]. > For more options, visit https://groups.google.com/d/optout. > -- 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.
