## Search found 4646 matches

Yesterday, 11:55
Forum: ElmerSolver
Topic: Change of behaviour of SaveScalars solver
Replies: 4
Views: 47

### Re: Change of behaviour of SaveScalars solver

Hi Olivier, This may have been intentional. This operator is a little problematic: Operator 2 = String "Boundary Sum" If the two boundaries share a node what should be done about it? You have alternatives to consider it fifty-fifty in both, consider it in both, or consider it randomly in e...
Yesterday, 11:33
Forum: ElmerSolver
Replies: 2
Views: 72

### Re: Off-diagonal blocks for AdvectionDiffusionSolver

Hi Marc, If you have an AdvectionDiffusionSolver then it has basically just one block. If you want to consider the implicit couplings of the three components you should generate an modified version of the solver with 3 components. Then you can interpret the resulting matrix equation Ax=b such that A...
21 Sep 2023, 19:22
Forum: ElmerSolver
Topic: Levelset method
Replies: 17
Views: 412

### Re: Levelset method

Hi Roland, Nice progress! Temperature is very kind as it allows to be used as levelset function eliminating a lot of the machinery. You can also make the body freeze if is cold Body Force Velocity 1 = 0.0 Velocity 1 Condition = Variable Temperature Real 0 1.0 1687.0 0.0 End And similarly for 2nd com...
18 Sep 2023, 14:30
Forum: ElmerSolver
Topic: Extract Stiffness Matrix of each Element for Topology Optimization
Replies: 1
Views: 94

### Re: Extract Stiffness Matrix of each Element for Topology Optimization

Hi Stefan, Usually we compute the gradient on-the-fly using the derivatives of the basis functions (often names dBasisdx) at the integration point and the nodal values of parameter. (Note that there are also more generic ways to treat the parameters. For example, the artificial densities perhaps sho...
18 Sep 2023, 14:15
Forum: ElmerSolver
Topic: Nonlinear system keywords and slave solvers
Replies: 1
Views: 82

### Re: Nonlinear system keywords and slave solvers

Hi

I think it depends. If you have your own custom split then it will depend whether the routine looking for the keyword is performed in called by master or slave solver. Note that the Newton keywords are generally applicable only if there is Newton linearization.

-Peter
14 Sep 2023, 13:26
Forum: General
Replies: 2
Views: 131

Hi Sure, write a model and compile it. elmerf90 -o MySolver.so MySolver.F90 then use it in .sif file: Procedure = "MySolver" "MySolver" This is the loaded dynamically at run-time. All the ~130 models under \$ELMERSRC/fem/src/modules are in fact also used in same fashion but are ju...
12 Sep 2023, 19:57
Forum: ElmerSolver
Topic: Levelset method
Replies: 17
Views: 412

### Re: Levelset method

Hi Roland, This work on phase surface + free surface is fairly old stuff even in Elmer. Would you have any references on how this is dealt in other codes today? I think we would need a completely new free surface solver operating on normal-tangential coordinate system. It should include two parts. O...
12 Sep 2023, 19:51
Forum: ElmerSolver
Topic: Triple Point Modeling for Phase Change _ follow up
Replies: 3
Views: 90

### Re: Triple Point Modeling for Phase Change _ follow up

Hi Roland The key problem with the TransientPhaseChange solver is that there it is assumed that the movement is only in vertical direction. See eq (35.3) in: https://www.nic.funet.fi/pub/sci/physics/elmer/doc/ElmerModelsManual.pdf When this solver was coined it was assumed that a feedback mechanism ...
12 Sep 2023, 15:10
Forum: ElmerSolver
Topic: how to set discretization in Elmer
Replies: 2
Views: 95

### Re: how to set discretization in Elmer

Hi If you have Lagrange/Serendipity-elements then what is used is the elements in the mesh file. All shapes are supported to 2nd degree, some shapes even up to 4th. More convenient way to increase basis power is to use hierarchical p-basis. This does not work for all solvers, but does for HeatSolveV...
09 Sep 2023, 20:08
Forum: ElmerSolver
Topic: Unable to get reasonable result for InductionHeating example in elmer-elmag
Replies: 3
Views: 121

### Re: Unable to get reasonable result for InductionHeating example in elmer-elmag

Hi, If input parameters are in SI units and mesh as well (m) then all results will also be in SI units. -Peter