Calcs and visuals for thermal viewing

About the development of the FEM module/workbench.

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freedman
Posts: 1598
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Location: Washington State, USA

Calcs and visuals for thermal viewing

Postby freedman » Fri Sep 25, 2020 2:56 am

I have no exposure to FEM here, is there a way to show thermal profiles for a mass? For instance, an aluminum block 3 inch square with power resistors screwed to it, calculating watts to hold temp at different ambients with different insulations. And the temp profile of the block in different machined forms.
Thank you
thschrader
Posts: 1843
Joined: Sat May 20, 2017 12:06 pm
Location: Germany

Re: Calcs and visuals for thermal viewing

Postby thschrader » Fri Sep 25, 2020 1:26 pm

freedman wrote:
Fri Sep 25, 2020 2:56 am
... is there a way to show thermal profiles for a mass? ...
Do you mean something like this?
2 materials (core and cooling fins), contour-plot done with paraview.
resistor_cooler.FCStd
(55.25 KiB) Downloaded 19 times
resistor_cooling.JPG
resistor_cooling.JPG (50.8 KiB) Viewed 616 times
Jee-Bee
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Location: Netherlands

Re: Calcs and visuals for thermal viewing

Postby Jee-Bee » Fri Sep 25, 2020 3:51 pm

I thought he meant the reverse. so aplied the heat to some surface and wait
freedman
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Location: Washington State, USA

Re: Calcs and visuals for thermal viewing

Postby freedman » Sat Sep 26, 2020 6:23 am

so applied the heat to some surface and wait
Yes, that is true, I have a temp sensor and controller. I'm looking at different aluminum blocks and what power supply I need. The input wattage is all based on insulation.
thschrader if you could do that, thank you.
Oh! this looks like a study for a while. I going to need some time.
Thanks
thschrader
Posts: 1843
Joined: Sat May 20, 2017 12:06 pm
Location: Germany

Re: Calcs and visuals for thermal viewing

Postby thschrader » Sat Sep 26, 2020 6:51 am

freedman wrote:
Sat Sep 26, 2020 6:23 am
...
thschrader if you could do that, thank you.
...
Sorry, I still dont understand what you mean
(thermodynamics was not my favorite subject in school… ;) )
In my model above, you can change the boundary condition.
Doubleclick on resistor in tree and change input from temperature to watt.
change_boundary_condition.JPG
change_boundary_condition.JPG (68.01 KiB) Viewed 521 times
thschrader
Posts: 1843
Joined: Sat May 20, 2017 12:06 pm
Location: Germany

Re: Calcs and visuals for thermal viewing

Postby thschrader » Sat Sep 26, 2020 8:23 am

For the record:
Thermo-mech analysis with elmer.
resistor_cooler_elmer.FCStd
(55.25 KiB) Downloaded 24 times
Next step:
Define a fluid region around the cooler and run cfd-thermomech
analysis with elmer. We will see...
Thats why I need the mesh visibility inside, see here
https://forum.freecadweb.org/viewtopic.php?f=18&t=50578
freedman
Posts: 1598
Joined: Thu Mar 22, 2018 3:02 am
Location: Washington State, USA

Re: Calcs and visuals for thermal viewing

Postby freedman » Wed Sep 30, 2020 6:03 pm

I threw together a model so we have something to look at. Blue is insulation (compressed urethane), Brown is aluminum. The bottom with the attached resistor would have an insulation cover. The top would be open to the air. The material put in the cup won't boil, actually another cup fits in the heater made of glass.
Attachments
cup11.JPG
cup11.JPG (57.03 KiB) Viewed 391 times
cup_11.FCStd
(190.42 KiB) Downloaded 16 times
thschrader
Posts: 1843
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Location: Germany

Re: Calcs and visuals for thermal viewing

Postby thschrader » Thu Oct 01, 2020 1:36 pm

cup_FEM.FCStd
(125.78 KiB) Downloaded 23 times
temp_field.JPG
temp_field.JPG (38.41 KiB) Viewed 302 times
freedman
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Location: Washington State, USA

Re: Calcs and visuals for thermal viewing

Postby freedman » Fri Oct 02, 2020 5:25 pm

Thanks, thschrader. Very cool. I'm reading and looking at videos as much as I can.