[Ticket #4617] Virtual elements

[Pauvres_honteux]

MKraska seams to have some knowledge in how to create virtual elements:
Virtual elements
and
possible virtual element example of internal code example

[Pauvres_honteux]

Request: issue #4617

[Pauvres_honteux]

Hi bernd and joha2.

Could Fem mesh: Create mesh groups in python be helpful in making "Virtual elements" come true?

[joha2]

Hi bernd and joha2.
Could Fem mesh: Create mesh groups in python be helpful in making "Virtual elements" come true?

Hi, sorry for my late response! The mesh groups in Python (and those in the GUI) may be used to collect certain elements and put them together to groups. You may also collect nodes in the groups, although - as far as I know -, there is no GUI function for that, yet. If those nodes are within one group, you may use this group to implement some constraint equations in your favorite FEM solver, e.g. Calculix. Because I have no experience with Calculix itself, I don't know how to do that. So, in principle the basic organizational stuff is there, but it still needs to be implemented. What do you think @bernd?

Best wishes
Johannes

[Pauvres_honteux]

... there is no GUI function for that, yet ...

Perhaps it's "just" a matter of creating that GUI then?

[bernd]

... there is no GUI function for that, yet ...

Perhaps it's "just" a matter of creating that GUI then?

Yes and some more tweaks here and there. Wit this commit a new constraint is added. It is not much just the right code at the right places ...

https://github.com/berndhahnebach/FreeC ... ac9fdf0968

it adds:
- a new FreeCAD GUI command
- a new FreeCAD FEM object
- a icon for it
- a tool to collect the FEM nodes and elements
- the methods for the solver writer to write it to the input file

[bernd]

Hi bernd and joha2.
Could Fem mesh: Create mesh groups in python be helpful in making "Virtual elements" come true?

Hi, sorry for my late response! The mesh groups in Python (and those in the GUI) may be used to collect certain elements and put them together to groups. You may also collect nodes in the groups, although - as far as I know -, there is no GUI function for that, yet. If those nodes are within one group, you may use this group to implement some constraint equations in your favorite FEM solver, e.g. Calculix. Because I have no experience with Calculix itself, I don't know how to do that. So, in principle the basic organizational stuff is there, but it still needs to be implemented. What do you think @bernd?

totally correct, With this one could implement it without creating a real FEM object and all the needed tweaks for a real FEM object like linked in the last post.

[Pauvres_honteux]

With this commit, a new constraint is added.

It adds:
- a new FreeCAD GUI command
- a new FreeCAD FEM object
- an icon for it
- a tool to collect the FEM nodes and elements
- methods for the solver to write it to the input file

Wohoo! (doing my happy dance)

[bernd]

But these are not the virtual elements. These just shows how they would have to be implemented.

[Pauvres_honteux]

But these are not the virtual elements. These just shows how they would have to be implemented.

Oohh... =O/
Well, name the happiness that lasts forever ...