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Hi

you have some issues because your 3D geometry has some "small features" that forces the mesh to be very detailed, you can either remove some of them from the CAD as probably they will have minor effects on the model, or you need a large computer with plenty of RAM and wait long ...

Other point, start meshing the glass rod, its thin and long, there you have different options, a sweep mesh would probably do, but then you need to convert the surface mesh where the glass rod interacts with the other parts

Then mesh all the inside rods correctly free tets should do, then mesh the two parts that interface with the rods and the glass section, and finally mesh the external parts in "normal" if possible. Now I must use "fine" to extremely "fine" because of these "small features" which leads to 0.5 Mega elements, you can probably lower that by a factor 4 at least by having "nicer" volumes

by the way, you need to define the "air" or gas or vacuum? volume between the parts, they will exchange energy by convection, conduction and or radiation, this region must be defined (try using COMSOL "caps" from latest version), or close the volume with your CAD

Do not forget to define materials for all domains, with all parameters demanded by the green "vu"s

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Good luck
Ivar

Dear Ivar,

Thank you very much for your reply.

For one time, I started meshing from the body then heater rods and finally glass tube, but in the last stage I got an error"Out of memory in meshing processing" while I am using 80G as hard and 4G as RAM.

I followed your suggestion but during swept meshing for glass tube, I got this error,"Unsupported topology of domain".
I chose glass tube as domain, upper part of glass tube as source face and bottom face as destination face.

Also, I want to know how I can convert the surface mesh where the glass rod interacts with the other parts

Kind regards

Mehrdad

Hi

the out of memory could come from a java heap size or other items, not necessarioly limited by your 80Gb, check the KB on the main web site.

When you sweep mesh you get prism or hex, and if you want to continue with free tet you need to "convert" the surfaces to triangles, there is a specific node for that in the mesh sub-nodes.

You have also the copy mesh and copy "n" fold if you define several identical elements in the destination in the latest release

sweep mesh requires quite some fixed rules, often you can simplify the meshing by cutting your volume into smaller parts, this adds a few internal boundaries, but this is seldom an issue

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Good luck
Ivar

Dear Ivar,

Thank you very much for your useful suggestion.

1-I followed your guideline for meshing all part of my geometry as and it was very useful but my main problem is The glass tube, because it has interfaces with other parts.

2-I meshed the glass tube with "Free triangular mode" and then convert all the geometry. I chose this method, because in swept mesh I don not know which faces I should select as source and destination.But I am not sure if I followed the right way.

3-But in study mode, I got errors such as:
1-"No mesh on domain 1 in geometry 1, mesh case 1", While domain1 is my glass tube.
2-"Not all domains are meshed."
3-Feature: Stationary Solver 1(sol1/s1)
4-Error: Failed to find a solution

4-I tried cap faces but every time I encountered to this error"Edges must form simple loops"

Could you please guide me in these problems, especially in swept mesh?

Thank you very much for your time

Mehrdad

Dear Ivar,

Thank you very much for your useful suggestion.

-I followed your guideline for meshing all part of my geometry as and it was very useful but my main problem is The glass tube, because it has interfaces with other parts.

-I meshed the glass tube with "Free triangular mode" and then convert all the geometry. I chose this method, because in swept mesh I don not know which faces I should select as source and destination.But I am not sure if I followed the right way.

-But in study mode, I got errors such as:
1-"No mesh on domain 1 in geometry 1, mesh case 1", While domain1 is my glass tube.
2-"Not all domains are meshed."
3-Feature: Stationary Solver 1(sol1/s1)
4-Error: Failed to find a solution

-I tried cap faces but every time I encountered to this error"Edges must form simple loops"

Could you please guide me in these problems, especially in swept mesh?

Thank you very much for your time

Mehrdad

Hi

when you manually mesh, do not forget to leave a last free tri/tet "all remaining" node to be sure you have meshed all volumes, it's easy to mesh the boundaries and then forget the volumes.

note: triangles quads are 3D boundary (surface mesh) and tet, prism & hex are 3D domain meshs

Check with the Mesh stat display

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Good luck
Ivar