Hi all,
Thank you for your reply.
Let me explain what I am trying to do and why.
I want to solve a transient heat transfer problem of the additive
manufacturing (AM) process. In AM processes, metal powder is deposited in
layers, and then a laser source scans each layer and melts and bonds the
powder to the layer underneath it. To simulate this layer by layer process,
I want to start with a grid that covers all the layers, but initially, only
the bottom-most layer is active and all other layers are inactive, and then
as time progresses, I want to activate one layer at a time. I read on this
mailing list that cell "birth" or "activation" can be done by changing a
cell from FE_Nothing to FE_Q using p-refinement. I was trying to keep all
cells of the grid initially to FE_Nothing except the bottom-most layer. And
then convert one layer at a time to FE_Q. My questions are:
1. Does this make sense?
2. I have to do two other things for this to work. (a) When a cell becomes
FE_Q from FE_Nothing, dofs that are activating for the 1st time, I need to
apply a non-zero initial value to those dofs. This is to simulation the
metal powder deposited at a specified temperature,. e.g. room temperature.
(b) the dofs, that were shared between a FE_Q and FE_Nothing cells before
the p-refinement and now shared between FE_Q and FE_Nothing cells after
refinement, should retrain their values from before the refinement.

Another way to simulation this process would be to use a cell "awaking"
process, instead of the cell "birth". I keep call cells FE_Q but apply a
very low diffusivity to the cells of the layers that are not yet "awake".
But this way, I have to solve a larger system in all time steps. I was
hoping to save some computation time, by only forming a system consists of
cells that are in the "active" layers only.

Please let me if this makes sense? Is there any other method in deal.ii
that can simulation such a process?
Thank you very much and happy holidays.
Kaushik


On Tue, Dec 29, 2020 at 12:26 PM Wolfgang Bangerth <bange...@colostate.edu>
wrote:

> On 12/28/20 5:11 PM, Marc Fehling wrote:
> >
> > In case a FE_Nothing has been configured to dominate, the solution
> should be
> > continuous on the interface if I understood correctly, i.e., zero on the
> face.
> > I will write a few tests to see if this is actually automatically the
> case in
> > user applications. If so, this check for domination will help other
> users to
> > avoid this pitfall :)
> >
>
> More tests = more better :-)
> Cheers
>   W.
>
> --
> ------------------------------------------------------------------------
> Wolfgang Bangerth          email:                 bange...@colostate.edu
>                             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 a topic in the
> Google Groups "deal.II User Group" group.
> To unsubscribe from this topic, visit
> https://groups.google.com/d/topic/dealii/ssEva6C2PU8/unsubscribe.
> To unsubscribe from this group and all its topics, send an email to
> dealii+unsubscr...@googlegroups.com.
> To view this discussion on the web visit
> https://groups.google.com/d/msgid/dealii/0398a440-3ee2-9642-9c27-c519eb2f12e5%40colostate.edu
> .
>

-- 
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/CAC-fs6tnRZ5LDwCts8uO1ZmH9u6dMkY4vWK8SANKKcXSAaBtjQ%40mail.gmail.com.

Reply via email to