Hi,
I'm trying to do some basic calculations using the StatCurrent solver.
I've got a simple geometry consisting of one smaller cubiod within one big cuboid. The two cuboids are different bodies and have a different conductivity. The boundary conditions are two different potentials at two opposing surfaces of the big cubiod.
The problem is: the result isn't influenced by the smaller cuboid at all. Regardless of what the conductivity of the inner cuboid is, the result is always the same. The inner cuboid always has a constant potential of 0 and no volume current.
I have attached my mesh and .sif files.
Does anyone have any idea where the problem might be?
Best regards
Stefan
ElmerSolver seems to ingore second body
Re: ElmerSolver seems to ingore second body
Hi,
it seems that the two bodies are not connected, i.e. the nodes at the interfaces are not the same for both bodies. How did you build your geometry and mesh? Which software did you use?
Matthias
it seems that the two bodies are not connected, i.e. the nodes at the interfaces are not the same for both bodies. How did you build your geometry and mesh? Which software did you use?
Matthias
Re: ElmerSolver seems to ingore second body
Hi,
I built my mesh using 2 .stl files, converting them to the Elmer Mesh format with netgen and merging them together with ElmerGrid.
Like this:
Best regards,
Stefan
I built my mesh using 2 .stl files, converting them to the Elmer Mesh format with netgen and merging them together with ElmerGrid.
Like this:
Code: Select all
netgen -batchmode -geofile='block_big.stl' -meshfile='block_big' -veryfine -meshfiletype="Elmer Format"
netgen -batchmode -geofile='block_small.stl' -meshfile='block_small' -veryfine -meshfiletype="Elmer Format"
ElmerGrid 2 2 block_small -boundtype 1 1 7
ElmerGrid 2 2 block_small -boundtype 2 2 8
ElmerGrid 2 2 block_small -boundtype 3 3 9
ElmerGrid 2 2 block_small -boundtype 4 4 10
ElmerGrid 2 2 block_small -boundtype 5 5 11
ElmerGrid 2 2 block_small -boundtype 6 6 12
ElmerGrid 2 2 block_big -bulktype 1 1 1 ! make bodies [1,1] to 1
ElmerGrid 2 2 block_small -bulktype 1 1 2 ! make bodies [1,1] to 2
ElmerGrid 2 2 block_small -in block_big -out merged_blocks -unite -merge 1.0e-10
Stefan
-
- Site Admin
- Posts: 4812
- Joined: 22 Aug 2009, 11:57
- Antispam: Yes
- Location: Espoo, Finland
- Contact:
Re: ElmerSolver seems to ingore second body
Hi Stefan
The "merge" option can only merge meshes that are conforming i.e. have nodes at the same location at the interface of interest. If you have no special strategy to ensure that then probably only a few corner nodes will be merged.
-Peter
The "merge" option can only merge meshes that are conforming i.e. have nodes at the same location at the interface of interest. If you have no special strategy to ensure that then probably only a few corner nodes will be merged.
-Peter
-
- Posts: 2237
- Joined: 25 Jan 2019, 01:28
- Antispam: Yes
Re: ElmerSolver seems to ingore second body
merge 1.0e-10
the value is the tolerance on merge. That is a fairly tight tolerance on a mesh that has nodal locations defined in the range of +/- 0.5
That value would be lost in the accuracy of the computer's ability to track significant digits.
If the smallest distance intended between nodes is 1.E-2 then the merge tolerance could be 1.E-4
the value is the tolerance on merge. That is a fairly tight tolerance on a mesh that has nodal locations defined in the range of +/- 0.5
That value would be lost in the accuracy of the computer's ability to track significant digits.
If the smallest distance intended between nodes is 1.E-2 then the merge tolerance could be 1.E-4
-
- Posts: 2237
- Joined: 25 Jan 2019, 01:28
- Antispam: Yes
Re: ElmerSolver seems to ingore second body
I imported the mesh into GMesh and the nodes between the bodies are far apart. The two bodies have to share the same nodes at the interface. The inner body is much finer than the outer body. Merge is not going to work for this mesh.