Is FEM Running?

[pbhuter]

I followed the details of this tutorial:

http://www.freecadweb.org/wiki/index.ph ... #Procedure

But I used my own part design. I get to creating the .inp file, and it seems to just stop. The time does not advance. This is what my screen looks like:

Screenshot_2016-08-18_17-14-28.png (157.48 KiB) Viewed 1430 times

I have done this several times, and no result. i have rebuilt my FEM analysis, and no result. My computer is running fine, and it seems FreeCAD is available to do other things, so I do not think it is running.

When I follow the tutorial exactly, I end up seeing constraints and forces applied to the cube. But when I do things in my model, I do not see these constraints or forces.

I did try letting it run for about five minutes, but it did not seem to be doing anything.

Suggestions?

OS: Ubuntu 16.04.1 LTS
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.16.6703 (Git)
Build type: None
Branch: releases/FreeCAD-0-16
Hash: 2ce5c8d2e3020d05005ed71f710e09e9aa561f40
Python version: 2.7.11+
Qt version: 4.8.7
Coin version: 4.0.0a
OCC version: 6.8.0.oce-0.17

[Korslight]

Hello pbhuter,

I recently tested out FEM for myself and I was able to get a simple simulation running.

If you attach your part and give me the constraints I will see if I can get it to run.

Cheers,
Korslight

[Korslight]

I attached a super simple simulation with I just did. So yes the FEM workbench is working.

I can run through it with you as well.

Let me know your thoughts.

[pbhuter]

I appreciate you getting back to my post.

I was able to get it to run when I went step-by-step through the example I posted. But with my part design, it does not work. I will post my part first thing tomorrow morning (or maybe late tonight).

[Korslight]

Yeah, that is strange. I will see if I can get it to run and if not I am sure there are people on here more proficient with the FEM that would be able to help you out.

Cheers

[PrzemoF]

Can you run FreeCAD from terminal and see if there are any error messages? If you can upload the file we'll test it.

I guess 6703 is the latest stable version for ubuntu, but there were _massive_ changes since then - current version is ~8291 (over 1500 commits of difference)

[pbhuter]

Here is my file.

I meshed both pieces of the part using the default parameters that show up when you click the "mesh" button.
I placed a surface constraint on the bottom face.
I placed a force of 3,625,000 N on the bottom face acting perpendicular to the face.
I applied a material with the following properties:
- 68.9 GPa
- 0.330
- 2700 kg/m^3

I wanted to upload the FEM file, but it is too big, so hopefully someone can recreate my set up and see if they can get it to run.

I appreciate the help!

[PrzemoF]

What's the size of the file?

[easyw-fc]

Can you run FreeCAD from terminal and see if there are any error messages? If you can upload the file we'll test it.

I guess 6703 is the latest stable version for ubuntu, but there were _massive_ changes since then - current version is ~8291 (over 1500 commits of difference)

Hi @PrzemoF
I tried FC latest in ubuntu 16.04.1 both 32 and 64bits under VB 5.0.26 (latest) but unfortunately I cannot use correctly FEM WB

Code: Select all

OS: Ubuntu 16.04.1 LTS
Word size of OS: 32-bit
Word size of FreeCAD: 32-bit
Version: 0.17.8293 (Git)
Build type: None
Branch: master
Hash: 51e23d854e59ab0a23a9ea9b19e74e5f02753d82
Python version: 2.7.12
Qt version: 4.8.7
Coin version: 4.0.0a
OCC version: 6.8.0.oce-0.17

then I did some test under windows as suggested by @bernd
viewtopic.php?f=18&t=16749&start=50#p133736
that seems a very useful workaround to work under windows...
and still I cannot obtain a thermomechanical analysis on i.e. these files
simplechip_05_multiple_mat.fcstd
from
viewtopic.php?f=18&t=16749&start=40#p133612
or
simple_chip.fcstd
from
viewtopic.php?f=18&t=16749&start=40#p133620

We are developing Thermo-mechanical training
http://opensim.co.za/index.php?option=c ... Itemid=618
Not complete but a start.

Never use first order tet elements !

Regards
Michael

@ makkemal would you mind to create a guide also for Thermo-mechanical analysis on i.e. something similar to a pcb with some chips?
thanks a lot for supporting
Maurice

[makkemal]

@Maurice
A windows version of 0.16 with thermo-mechanical included can be found here
http://opensim.co.za/index.php?option=c ... Itemid=618
To simplify chip analysis need a few improvements on multi-body meshing
viewtopic.php?f=18&t=16750
One of my guys is working on including radiation heat transfer

Get a unbuntu machine