Very Simple Thermal Model of Cylindrical Rod

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PerdixInc
Posts: 7
Joined: Tue Dec 24, 2019 4:12 pm

Very Simple Thermal Model of Cylindrical Rod

Post by PerdixInc » Tue Dec 24, 2019 5:07 pm

Greetings!
I am attempting to make a simple thermal model of a cylindrical rod. The idea is that the problem is essentially one dimensional and you can use the equations in Halliday and Resnik to compare the FEM results. There are only three boundary conditions, both ends and the curved cylindrical surface. By changing the initial temperature, thermal conductivity or flux at the surfaces, you can simulate the effects of heating, insulation, and being in a constant radiative bath.
(1) I cannot create new material in the materials editor, and get the results to come up in the materials window. I've added correct thermal conductivity parameters to the editor, and attempted to save, then re-pull the just entered parameters. It doesnt work.
(2) I cannot ascribe the materials to the cylindrical rod. The examples I've pulled off you tube either dont work, or the presentation is soooo garbled I cannot understand. I am willing to post a simple model in the future.

This problem is not rocket science. Thanks!
PerdixInc


OS: Windows 10
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.18.16131 (Git)
Build type: Release
Branch: releases/FreeCAD-0-18
Hash: 3129ae4296e40ed20e7b3d460b86e6969acbe1c3
Python version: 3.6.6
Qt version: 5.6.2
Coin version: 4.0.0a
OCC version: 7.3.0
Locale: English/UnitedStates (en_US)
Attachments
FreeCad Thermal Test 1223192127.FCStd
(399.26 KiB) Downloaded 7 times
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Kunda1
Posts: 6355
Joined: Thu Jan 05, 2017 9:03 pm

Re: Very Simple Thermal Model of Cylindrical Rod

Post by Kunda1 » Tue Dec 24, 2019 5:10 pm

Please use the latest 0.19dev for any FEM based operations
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PerdixInc
Posts: 7
Joined: Tue Dec 24, 2019 4:12 pm

Re: Very Simple Thermal Model of Cylindrical Rod

Post by PerdixInc » Tue Dec 24, 2019 10:40 pm

Hi-thank you for the prompt reply.

I have not made it past the 0.19 pre install. I managed to get the Zip file FreeCAD-0.19_pre downloaded to my machine from https://github.com/FreeCAD/FreeCAD/rele ... g/0.19_pre. I downloaded the file FreeCAD_0.19.19036_x64_LP_12.1.2_PY3QT5-WinVS2015.7z

I started looking around for an .exe file to start the program in the exploded files. I have not found an .exe

If I did not download the proper file, can you send me the correct link and some instructions? I am not getting very far here, and I noticed where one other Gentleman was unable to find an executable for his 0.19 pre.

I did not find a 0.19 dev as you suggested

Thank you
PerdixInc
ulrich1a
Posts: 1920
Joined: Sun Jul 07, 2013 12:08 pm

Re: Very Simple Thermal Model of Cylindrical Rod

Post by ulrich1a » Wed Dec 25, 2019 1:36 pm

PerdixInc wrote:
Tue Dec 24, 2019 10:40 pm
I have not found an .exe
The FreeCAD.exe is inside of the folder "bin". Scroll down until you find the executable binary between all delivered dlls.

But you may be out of luck. It was reported that the two last published versions have a problem: https://forum.freecadweb.org/viewtopic.php?f=4&t=41929

Ulrich
thschrader
Posts: 1478
Joined: Sat May 20, 2017 12:06 pm
Location: Germany

Re: Very Simple Thermal Model of Cylindrical Rod

Post by thschrader » Wed Dec 25, 2019 2:39 pm

PerdixInc wrote:
Tue Dec 24, 2019 5:07 pm
(2) I cannot ascribe the materials to the cylindrical rod. The examples I've pulled off you tube either dont work, or the presentation is soooo garbled I cannot understand. I am willing to post a simple model in the future.

This problem is not rocket science. Thanks!
PerdixInc
doubleclick on "steel" in model-tree for adjusting the thermomechanical parameters.
For me your file runs.
thermal.FCStd
(8 KiB) Downloaded 10 times
test_run.JPG
test_run.JPG (56.34 KiB) Viewed 287 times
PerdixInc
Posts: 7
Joined: Tue Dec 24, 2019 4:12 pm

Re: Very Simple Thermal Model of Cylindrical Rod

Post by PerdixInc » Wed Dec 25, 2019 7:49 pm

Hi-thank you for taking a look at me FEM Thermal file. It is nice to know that it worked and that I am not a complete idiot! The actual thermal problem I want to model is quite complicated. This is just a start.

The present version of 0.19 Pre apparently is corrupted, or is an incomplete build. There is no executable file in any "bin" folder. There are other postings on this subject.

What is the probability that you help me obtain a copy of your FreeCad 0.19 build? Can we post it on the FreeCad Forum, or is there another way?

Thank you for your help in this matter

PerdixInc
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bernd
Posts: 8959
Joined: Sun Sep 08, 2013 8:07 pm
Location: Zürich, Switzerland

Re: Very Simple Thermal Model of Cylindrical Rod

Post by bernd » Wed Dec 25, 2019 8:18 pm

PerdixInc wrote:
Wed Dec 25, 2019 7:49 pm
What is the probability that you help me obtain a copy of your FreeCad 0.19 build? Can we post it on the FreeCad Forum, or is there another way?
Just wait a few days and it will be fixed.
PerdixInc
Posts: 7
Joined: Tue Dec 24, 2019 4:12 pm

Re: Very Simple Thermal Model of Cylindrical Rod

Post by PerdixInc » Fri Dec 27, 2019 12:16 am

Greetings!
I downloaded the 0.19 as shown below, and I got it extracted and it actually runs! We will see how far I get in the FEM analysis
Now I need a brain stem cell transplant from a proficient FreeCad expert.
Anyone want to make a donation?
Thank you!
PerdixInc

OS: Windows 10 (10.0)
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.19.19066 (Git)
Build type: Release
Branch: master
Hash: c766d757912ded11d41bc825f82c47a8428396ad
Python version: 3.7.3
Qt version: 5.12.5
Coin version: 4.0.0a
OCC version: 7.3.0
Locale: English/United States (en_US)
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