On 2/8/21 11:06 AM, Karthikeyan Chockalingam wrote:
Q1) I am not familiar with RE_RaviartThomas elements, is it a vector type
element having dim components,
that is how I see it used in step-20 to represent components of velocities?
Yes.
Q2) How does my FE_System for u and \sigma together look like, let's say I
modify step-8 as?
If RT elements have dim components, then the following system wouldn't make
sense.
FE_System(FE_Q<dim>(degree), dim, FE_RaviartThomas<dim>(degree), dim*dim)
or the below
FE_System(FE_Q<dim>(degree), dim, FE_RaviartThomas<dim>(degree), dim)
The latter.
I had misunderstand that you didn't actually want to use FE_RT. You can also do
FE_System(FE_Q<dim>(degree), dim, FE_Q<dim>(degree), dim*dim)
which is probably closer to your intention.
Q3) Such a system can only be solved using BlockMatrix and BlockVector i.e not
using components alone?
I ask this question because I gather from different postings that PETSc
does not work with Block format.
Blocks are just a convenient way to subdivide a linear system if you want to
compose solvers based on these blocks. If you want to solve a linear system as
a whole, don't use block solvers.
Q4) How do I group components into tensors? Is there a tutorial where a
_tensor system is solved_ you can point me to?
I don't think there is, but it works the same way as it does for vectors. You
might want to read through the vector-valued problems module and the relevant
tutorials.
Best
W.
--
------------------------------------------------------------------------
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/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/58047a0d-2060-ff2c-034d-7539fb726639%40colostate.edu.
