Hi,
I have thought about the problem again and now I have a solution proposal:
[[ u_i ]] = 0,
would I fulfill by adding entries in the constraint matrix.
E.g. u_i = u_j for each DoF pair on the boundary. I just have to figure out
the DoF indices i and j.
The average overall stress state, I want also archive with the constraint
matrix:
For the first DoF of the periodic boundary pair I would add a constrain
like
u_1 = A_1i u_i + A_1j u_j + ... + A_1N u_N + S_kl N_l
u_1 = sum_i^N ( A_1i u_i ) + S_k N_l
with i=2..N (all DoF indices on the periodic boundary), the prescribed
stress tensor S and a global normal vector of the boundary N.
And the coefficients are the the calculated by
A_ij = C_ijkl sym(u_k,l) n_j Jwxq
on the corresponding faces by iterating in standard fashion over all
cells/faces and evaluating the terms with via FEFaceValues.
[[ t_i n_i ]] = 0 should thereby be indirectly satisfied.
But I'm not sure if the evaluating the coefficients in such a manner, leads
in the end to the wanted behavior of the system (stress fluctuations on the
boundaries but an average prescribed stress tensor).
Is it a good idea to include coefficients in the constraint matrix that
depends on some shape function. I thought those belonged in the system
matrix.
Can this still work?
Another issue is how to make this concept work in a parallel context: Which
process must know about which DoF?
Regards,
Lukas Schöller
--
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 dealii+unsubscr...@googlegroups.com.
To view this discussion on the web visit
https://groups.google.com/d/msgid/dealii/ad96305f-99d0-4ca4-b37e-b68b0f0f9f93%40googlegroups.com.
