Hi,
I am trying to implement a DG version of Stokes equation. To calculate the boundary-fluxes on each face, how do I write it? I use a central flux discretization. The jump terms are easy,
jump_u = u-u.Other()
jump_v = v-v.Other()
But when it comes to the central flux my first idea is to use
flux_u = 0.5 * n * (grad(u) + grad(u.Other())
and likewise for v. This however gives me
NgException: T_MultVecVec : dimensions don’t fit
One version which does not give me an error is
flux_u = 0.5*(grad(u) + grad(u.Other()))n
flux_v = 0.5(grad(v) + grad(v.Other()))*n
However, I tested to calculate the matrix for the bilinear form
SymbolicBFI(-flux_u*jump_v, BND, skeleton=True)
when the FE-space is a vectorH1 space with dgjumps=False. The matrix has a non-zero norm, which is odd since the functions are continuous.
Note: the main idea is to use it for H(div) conform spaces
I would be immensely grateful for any help.