Search found 4185 matches

by raback
Today, 00:42
Forum: ElmerSolver
Topic: Problem to display results from second order elements
Replies: 8
Views: 85

Re: Problem to display results from second order elements

Hi Rich, Very helpful. Comparing the two you see Elmer version is missing the code for repermutation. For Gmsh this can be found to be (for 11 node tet): int tetGmsh[11] = {0,1,2,3,4,5,8,6,7,10,9}; When you look at ElmerGrid code for Gmsh you see (for 10 node tet): int order510[]={0,1,2,3,4,5,6,7,9,...
by raback
Yesterday, 12:35
Forum: ElmerSolver
Topic: Problem to display results from second order elements
Replies: 8
Views: 85

Re: Problem to display results from second order elements

Hi Jeremie, There is a bug in the Elmer export of netgen regarding 2nd order elements. The ordering is not correct. I sent a bug report some years ago but I guess Joachim has better things to do. The numbering convention is part of each mesh format so in that regard the problem is on netgen side. Yo...
by raback
Yesterday, 10:57
Forum: Installation & compilation
Topic: How to debug my solver
Replies: 2
Views: 40

Re: How to debug my solver

Hi Marc,

I think that if you have conflicting flags then the latter one usually prevails (in gnu compiler stack). So your first assumption should be ok.

I found a discussion on the topic that may be relevant:
https://stackoverflow.com/questions/405 ... tches-to-g

-Peter
by raback
14 Sep 2021, 23:00
Forum: ElmerSolver
Topic: Problem to display results from second order elements
Replies: 8
Views: 85

Re: Problem to display results from second order elements

Hi Just checked the numbering of second order tris/tets of vtk and they seem to be exactly the same as for Elmer. VtkTet.PNG Now the observation of Rich makes me wonder where the mesh came from, and whether you're sure the initial ordering provided to Elmer follows the same convention. Gmsh, for exa...
by raback
14 Sep 2021, 00:50
Forum: ElmerSolver
Topic: Smart Heater Control
Replies: 8
Views: 138

Re: Smart Heater Control

Hi The timestep may be a function. How about checking min/max temperature and the related heating/cooling speed. Then you could come up with a simple heuristics to shorten the timestep if you're about to pass. I wrote a possible UDF for timestep size. Didn't test it, not even compiled. Just to give ...
by raback
11 Sep 2021, 02:20
Forum: ElmerSolver
Topic: Smart Heater Control
Replies: 8
Views: 138

Re: Smart Heater Control

Hi The smart heater is really smart in the sense that tunes the heat load exactly so that the linearized system gives the correct value for the control temperature. Now in steady-state this works perfectly. If there are nonlinearities they just add some iterations but the overall operation works fin...
by raback
09 Sep 2021, 01:12
Forum: Software development
Topic: Itterating over vertically aligned nodes
Replies: 3
Views: 58

Re: Itterating over vertically aligned nodes

Hi The algo seems to rely on certain node numbering of the layers. So you are implicitely assuming something for 404 elements. For 408 elements this is not as easy as the midlayers have fever nodes. For 409 elements you can again have this kind of favorable numbering. Maybe this could be an option? ...
by raback
07 Sep 2021, 16:20
Forum: ElmerGUI
Topic: Magnetization
Replies: 6
Views: 128

Re: Magnetization

Rich, I think he is using edge elements which are quite different from the nodal elements that may be used in most other modules. To be more specific, the scalar potential is given in nodes but the vector potential that is here more relevant is solved using the edge element basis.

-Peter
by raback
07 Sep 2021, 15:31
Forum: ElmerGUI
Topic: Magnetization
Replies: 6
Views: 128

Re: Magnetization

Hi 1) Maybe somebody else can comment on this... 2) No need to worry here. The Post solves different fields using galerkin method and each field has different norm. So the convergence plot does not really make sense here. 3) Yes, it seems that the "quadratic approximation = true" keyword i...
by raback
26 Aug 2021, 12:17
Forum: ElmerSolver
Topic: Reinitialize fields during steady-state simulation?
Replies: 2
Views: 160

Re: Reinitialize fields during steady-state simulation?

Hi Is this related to AV solver and coupled iterations with it? This is the only solver where such "cumulation" might happen due to the Coulomb gauge not being enforced. There is sort of gauging that comes from the Krylov methods but as it is not enforced the solution might be polluted. If...