Search found 4707 matches

17 Nov 2023, 22:07
Forum: ElmerSolver
Topic: Meaning of routine GetNOFColours
Replies: 1
Views: 42

Re: Meaning of routine GetNOFColours

Hi When you use threads you can assemble several elements at the same time such that each thread treats one element at a time. To avoid the race conditions i.e. issues that appear when several threads try to write on the same memory locations something needs to be done. The idea is to split the mesh...
17 Nov 2023, 21:57
Forum: ElmerPost
Topic: Compute or store the CRS matrices
Replies: 11
Views: 317

Re: Compute or store the CRS matrices

Hi It is a tuple because CRS matrix may then be written as a regular Nx3 matrix. This is convenient to read with any other software. Still internally it is treated in CRS format. List matrix is a "singly linked list" such that each row has its own list. The nice thing with list structure i...
16 Nov 2023, 19:09
Forum: ElmerSolver
Topic: Residual stress on the inner pipe wall and boundary conditions
Replies: 12
Views: 257

Re: Residual stress on the inner pipe wall and boundary conditions

Hi,

To fix rigid body motion one could perhaps also add a small "Spring" to the BCs. So small that it will not affect the results but yet so big that the linear solvers converge to a unique solution.

-Peter
16 Nov 2023, 19:04
Forum: ElmerSolver
Topic: 2D induction cold crucible with impedance boundary conditions
Replies: 30
Views: 529

Re: 2D induction cold crucible with impedance boundary conditions

Hi Roland,

I guess it will be a form of Robin boundary condition. I think MATC is not sufficient since there will be some implicit terms too. But I'm also sure that somehow it can be expressed in terms of A_phi and involve adding a few lines of code.

BR, Peter
16 Nov 2023, 12:53
Forum: ElmerSolver
Topic: 2D induction cold crucible with impedance boundary conditions
Replies: 30
Views: 529

Re: 2D induction cold crucible with impedance boundary conditions

Hi

Sure it could be done. Just not in this form since the only field we are solving for in 2D is A_phi. In 3D we are solving for both A and V and the BC looks probably quite different.

-Peter
15 Nov 2023, 23:32
Forum: ElmerSolver
Topic: 2D induction cold crucible with impedance boundary conditions
Replies: 30
Views: 529

Re: 2D induction cold crucible with impedance boundary conditions

Hi Roland, Unfortunately this feature is only available in 3D (where it is often essential). -Peter
15 Nov 2023, 17:49
Forum: ElmerSolver
Topic: Transient acoustic problem with large number of elements
Replies: 8
Views: 269

Re: Transient acoustic problem with large number of elements

Hi I would not do it before really needed. Changing all "integer" in the code "integer(kind=int64)" is probably not a good idea. It will make the code slover and probably there will a lot of places where the API to other libraries will be broken. Most libraries work with int32. G...
15 Nov 2023, 17:24
Forum: ElmerSolver
Topic: Maximum number of exported variables
Replies: 3
Views: 137

Re: Maximum number of exported variables

Hi,

With this old code you need to cast it:

Exported Variable 21 = String "myvar"

-Peter
11 Nov 2023, 00:21
Forum: ElmerGUI
Topic: How do you add a new solver?
Replies: 4
Views: 3371

Re: How do you add a new solver?

Hi, There is a version for density functional theory, DFTSolver.F90, among the code and apparently H20 molecule in test case dft_water. When this was done lo...ong ago FEM had not been applied too much for DFT. No the situation is quite different. There are a lot of code doing quantum mechanics also...
10 Nov 2023, 23:50
Forum: ElmerSolver
Topic: Transient acoustic problem with large number of elements
Replies: 8
Views: 269

Re: Transient acoustic problem with large number of elements

Hi The largest 32 bit signed integer is 2,147,483,647 so that indeed may set an upper limit. I guess there are not too many places where this should be replaced but this has not been in focus. I think the nodes are given a parallel global numbering. You will probably face other issues before that. W...