Thermal Analysis Of a Fluid

[bernd]

another example https://forum.freecadweb.org/viewtopic. ... 30#p194708

[tthomas20]

Awesome, this is the first example I've seen that actually uses a fluid thermal analysis. However, I am unfamiliar with the Elmer solver. What is the difference between that and CalculiX?

Also, when I try to activate the mesh and write the file to run the solver, I get this display

Thermal Analysis of a Fluid Picture_1.PNG (113.02 KiB) Viewed 964 times

The tree view says its a gmesh already but I cannot open parameters such as the mesh, material cards, etc. I can only open the solver functions and the inlet temperature condition

[bernd]

the file is before release 0.17 .. That was a time with steady changing API in FEM. I get some errors on file opening due to this ...

Code: Select all

 
<string>(1)<class 'ModuleNotFoundError'>: No module named 'PyObjects'
<string>(1)<class 'ModuleNotFoundError'>: No module named 'PyObjects'
<string>(1)<class 'ModuleNotFoundError'>: No module named 'PyObjects'
<string>(1)<class 'ModuleNotFoundError'>: No module named 'PyObjects'
<string>(1)<class 'ModuleNotFoundError'>: No module named 'PyObjects'
Enumeration index -1 is out of range, ignore it
<string>(1)<class 'ModuleNotFoundError'>: No module named 'PyGui'
<string>(1)<class 'ModuleNotFoundError'>: No module named 'PyGui'
<string>(1)<class 'ModuleNotFoundError'>: No module named 'PyGui'
<string>(1)<class 'ModuleNotFoundError'>: No module named 'PyGui'
<string>(1)<class 'ModuleNotFoundError'>: No module named 'PyGui'

these objects needs to be recreated ... I may have a look ...

[bernd]

try to play with this https://forum.freecadweb.org/viewtopic. ... 10#p222406 It opens fine for me. But I would read the following posts too.

Ahh FreeCAD FEM is capable of using different FEM solvers. Standard solver is CalculiX. But it works with ElmerFEM, Z88 and OOFEM (but z88 and OOFEM only very basic) too.


bernd

[bernd]

reas the following 20 posts of the link! Afterwards you should know which file to take and how to run it!

[tthomas20]

I have been reading through the forum discussion you gave me and trying to run the Elmer solver but it tells me it cannot find the binary. I have looked in my FC folders and I do not see an .exe for Elmer like there is for CalculiX.

Is there a set up that needs to happen? If so, I have not been able to find an explination

Thanks for your help

Elmer Settings.PNG (115.5 KiB) Viewed 923 times

No Elmer Binary.PNG (64.46 KiB) Viewed 923 times

[bernd]

elmer is not provided with FreeCAD. You need to install it youself, which is easy if you are on Windows. http://www.nic.funet.fi/pub/sci/physics ... n/windows/ After installation you need to set the path to elemer fem binary and elmer grid binary in FEM prefs.

Bernd

[tthomas20]

Oh ok. That answers a lot of questions. Its a little misleading since there is already an Elmer option in the FEM settings.

I will get on downloading it and playing with the examples and I'll let you know how it goes.

Thanks!

[tthomas20]

Just an update on the solver...I installed Elmer with no problem and set the path to the correct binary and that took care of that problem. After remeshing and writing the file I get the error saying the solver ignored my flow constraints (which I found on the forum means it didn't register my constrains for some reason...still don't know why)

Elmer Ignored Constraints.PNG (37.3 KiB) Viewed 867 times

Also, when I attempt to recreate the heat and flow constrains under the Elmer solver, it will not let me select anything and gives me this report when I click "Add"

Code: Select all

Traceback (most recent call last):
  File "C:\Users\tthomas\AppData\Local\FreeCAD 0.18\Mod\Fem\femguiobjects\FemSelectionWidgets.py", line 83, in _add
    selection = self.getSelection()
  File "C:\Users\tthomas\AppData\Local\FreeCAD 0.18\Mod\Fem\femguiobjects\FemSelectionWidgets.py", line 156, in getSelection
    for sub in self._getObjects(selObj.Object, selObj.SubElementNames):
  File "C:\Users\tthomas\AppData\Local\FreeCAD 0.18\Mod\Fem\femguiobjects\FemSelectionWidgets.py", line 167, in _getObjects
    shape = obj.Shape
AttributeError: 'FeaturePython' object has no attribute 'Shape'

Other than that, the solver ran and gave me a result mesh that I could format, but it only has the heat constraints