Calculate mean heat flux through a wall: is It possible?

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kensan
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Joined: Wed Nov 30, 2022 7:23 pm

Calculate mean heat flux through a wall: is It possible?

Post by kensan »

Hi,
I have find FreeCAD and have start to learn the basic elements. I'm interested in building insulation and the heat loss of walls, thermal bridges, windows, floors, etc, etc. Is It possible with FreeCad to calculate the amount of heat passing through a thermal bridge given an internal temperature and an external temperature?

In a post with title "FEM: How to create model with multiple materials" in year 2016 @Christoph said:
Hi Harald,
FreeCAD Fem Workbencb can calculate temperature distributions using thermo mechanic, i.e. it should be possible to display the temperature distribution in building envelopes (thermal bridges as concrete floores, corners etc.). But its not possible to display heat flux density or calculate mean heat flux through a wall.
https://forum.freecadweb.org/viewtopic. ... 65#p193065

Now with the last version of Freecad (0.18.6) is possible to calculate mean heat flux through a wall or through a multimaterial 3D building object?
Tank You.
chrisb
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Re: Calculate mean heat flux through a wall: is It possible?

Post by chrisb »

Moved from Help forum.

0.18 is utterly outdated, and FEM has evolved significantly. Consider to update to 0.20 or even 0.21.
A Sketcher Lecture with in-depth information is available in English, auf Deutsch, en français, en español.
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NewJoker
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Re: Calculate mean heat flux through a wall: is It possible?

Post by NewJoker »

When it comes to thermal output variables, FreeCAD still calculates only temperatures. To create a contour plot of heat flux you would have to export the .inp file and add HFL to *EL FILE. Then postprocess in other software (like GraphiX).
kensan
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Re: Calculate mean heat flux through a wall: is It possible?

Post by kensan »

chrisb wrote: Wed Nov 30, 2022 8:03 pm Moved from Help forum.

0.18 is utterly outdated, and FEM has evolved significantly. Consider to update to 0.20 or even 0.21.
Sorry form my bad section choice. If needed i Will update FreeCad. My linux box have in its repository only 0.18.6 version.
kensan
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Joined: Wed Nov 30, 2022 7:23 pm

Re: Calculate mean heat flux through a wall: is It possible?

Post by kensan »

NewJoker wrote: Wed Nov 30, 2022 8:33 pm When it comes to thermal output variables, FreeCAD still calculates only temperatures. To create a contour plot of heat flux you would have to export the .inp file and add HFL to *EL FILE. Then postprocess in other software (like GraphiX).
TY,
I hoped in Freecad fo the calculation of thermal bridges of my home with FEM. The specific programs for this calculation are much easier from what I have seen, so I will learn to use Freecad not for this calculation.
chrisb
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Re: Calculate mean heat flux through a wall: is It possible?

Post by chrisb »

kensan wrote: Wed Nov 30, 2022 10:42 pmMy linux box have in its repository only 0.18.6 version.
We know this problem, but cannot do much about it. Download a stable AppImage from the download page or an even more recent version from here: https://github.com/FreeCAD/FreeCAD-AppI ... kly-builds.
A Sketcher Lecture with in-depth information is available in English, auf Deutsch, en français, en español.
kensan
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Joined: Wed Nov 30, 2022 7:23 pm

Re: Calculate mean heat flux through a wall: is It possible?

Post by kensan »

chrisb wrote: Wed Nov 30, 2022 10:55 pm
kensan wrote: Wed Nov 30, 2022 10:42 pmMy linux box have in its repository only 0.18.6 version.
We know this problem, but cannot do much about it. Download a stable AppImage from the download page or an even more recent version from here: https://github.com/FreeCAD/FreeCAD-AppI ... kly-builds.
I'm dowloading appimage, I suppose it works in my linux box. By the way I can donate via SEPA bank transfer: very good. I will consider a donation. I had learn how to draw in Openscad, so FreeCAD is a good option for me to improve my 3D skills.
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