Curve cleanup

[aleximos]

Hello!
New to FEMAP and I'm having a problem with very small redundant curves, after editing my surfaces. I tried different commands like Geometry-Midsurface-Cleanup or Mesh-Geometry Preparation, in order to clean these redundant curves, but couldn't solve it.
The weird is that if I select all the curves and then delete, won't delete them. But if I select each one manually, then they can be deleted. But I cannot do that manually for the whole model.
I'm sending you a small example as attachment. Any help is appreciated

 

[Naffoussi]

Hi aleximos,

You have to use the Geometry / Surface / Non-Manifold add. this is a powerful tool when creating midsurfaces. it will "merge" all duplicated curves and create a general body. Free-edges will be highlighted in yellow and then when you mesh your model you can be sure that all interfaces between sheets will be merged automatically.

Go to the Femap help under :

3.3.3.14 Geometry, Surface, NonManifold Add...
...is the only command in FEMAP which allows you to create “Non-Manifold Solid Geometry”, an option in the Parasolid modeling kernel which creates “General Bodies” as opposed to regular solids (FEMAP solids) and sheet solids (FEMAP surfaces). The command allows you to Boolean Add sheet solids to one another, as well as add “sheet solids” to Parasolid “solids”. The “Non-Manifold Add Tolerance” may be adjusted in an attempt to have more solids and sheet solids combined into as few “general bodies” as possible. (see the help to learn more...)


hope this helps,
SN

 

[Naffoussi]

For the small curves you can use the meshing tool box / combined/composite curves / by point. this will create one curve based on the point you choose.

 

[aleximos]

Thanks for your immediate answer!
While using the command Non-Manifold add is there any option to control which points must remain stable?

 

[Naffoussi]

I don't understand what do you mean by stable points?
If it is about some free edges you want to keep...you can merge them all and then use the mesh / connect / Unzip ...to disconnect the elements you want.
The unzip command allows you to choose between :
- None : a second node is created.
- Rigid elements: you can create directly RBE2 with two coincident nodes at this location
- Spring damper (CBUSH)
- DOF Spring elements
...

Regards,
SN

 

[aleximos]

When using the Non-Manifold add to merge 2 free edges that are not coincident, you give a tolerance the distance between them (e.g t = 0,05). In order to merge, the one's edge points will move t. So my question is, how I can control, which are moving?

 

[Naffoussi]

I think you could not control it. Curves must be close enough to allow the non-manifold add operation. (I don't know how exactly Femap do it, you can try on a simple model...)
You have to prepare the mid-surfaces before using this command. You can use the "mid-surface automatic" or the "mid-surface extend" commands...
Then you can use the non_manifold add.

Regards,
SN

 

[aleximos]

Sometimes when I use the non-manifold add command, I get this error msg "Invalid Body after adding Solid xxx , it is being skipped". Any ideas?

 

[Naffoussi]

What command have you done before it displays the error message? Adding a second solid to an existing "General body"?

Seif Eddine Naffoussi, Stress Engineer

http://www.Innovamech.com

33650 Martillac – France

 

[aleximos]

General body is the result from a non-manifold add?

 

[Naffoussi]

Yes

Seif Eddine Naffoussi, Stress Engineer

http://www.Innovamech.com

33650 Martillac – France

 

[aleximos]

Probably I did add a second solid to an existing "General body". Is this a problem?

 

[Naffoussi]

I don't know exactly if this is problem but I know that is preferred to add all geometry at the same time (or adding independent solids then connect them).
Because since you add all solids to a general body you could not do some tasks anymore and you have to go back using Recover non-manifold add...

Regards,
SN

Seif Eddine Naffoussi, Stress Engineer

http://www.Innovamech.com

33650 Martillac – France

 

[aleximos]

The problem is that I'm trying to add 2 general bodies into one, but sometimes works and sometimes doesn't.

 

[Naffoussi]

Try to recover all solids and redo the non-manifold add. It will may be works...



Seif Eddine Naffoussi, Stress Engineer

http://www.Innovamech.com

33650 Martillac – France